Technology

9.7.4 Leash CodeHS Answers: Complete JavaScript Solution

Published

2 months ago

September 15, 2026

Admin

If you are looking for 9.7.4 leash codehs answers, the main task is simple once you understand mouse events. The exercise asks you to place a ball on the canvas, connect it to the center with a line, and make the ball follow the mouse. The line acts like a leash because one end stays fixed while the other moves with the ball.

This guide gives the full solution, but it also explains why each line is needed. That matters. Copying code may finish the exercise, but knowing how it works will help with later CodeHS graphics problems.

The 9.7.4 leash codehs answers solution mainly uses Circle, Line, mouseMoveMethod(), and mouse-event coordinates. Once those pieces work together, the program becomes short and easy to read.

What the Leash Exercise Is Asking You to Build

The Leash exercise is a JavaScript graphics task. You begin with a circle placed in the center of the canvas. A line also starts from that same center point. When the mouse moves, the circle follows the pointer while the far end of the line follows it too.

The center end of the line does not move. That creates the leash effect.

Most students searching for 9.7.4 leash codehs answers are really trying to solve three small problems: how to find the canvas center, how to track the mouse, and how to update a line while the program is running.

Complete Code for the Exercise

Here is the full working solution:

// Constant for the ball's radius
var BALL_RADIUS = 30;

// Global variables to track the ball and the leash line
var ball;
var line;

function start() {
    var centerX = getWidth() / 2;
    var centerY = getHeight() / 2;

    ball = new Circle(BALL_RADIUS);
    ball.setPosition(centerX, centerY);
    ball.setColor(Color.yellow);
    add(ball);

    line = new Line(centerX, centerY, centerX, centerY);
    add(line);

    mouseMoveMethod(leash);
}

function leash(e) {
    ball.setPosition(e.getX(), e.getY());
    line.setEndpoint(e.getX(), e.getY());
}

This version of 9.7.4 leash codehs answers keeps the code compact. It also follows the normal CodeHS graphics pattern: create objects in start(), store them in global variables, then change those objects inside an event function.

Why BALL_RADIUS and Global Variables Matter

The line var BALL_RADIUS = 30; gives the circle a radius of 30 pixels. Using a named value makes the code easier to change later.

You could write new Circle(30), and the program would still work. But a constant makes the purpose clearer. If you want a larger ball, you only need to change one value.

In many CodeHS lessons, this style helps separate setup values from the main program logic. It also makes 9.7.4 leash codehs answers easier to understand when you return to the code later.

The variables ball and line are also declared outside the functions:

var ball;
var line;

This matters because both start() and leash(e) need access to the same objects.

If you create the ball only as a local variable inside start(), the leash() function may not be able to use it. The same issue applies to the line.

Global variables let the program create the graphics once and then change them whenever the mouse moves.

Finding the Exact Center of the Canvas

The program uses these two lines:

var centerX = getWidth() / 2;
var centerY = getHeight() / 2;

getWidth() returns the width of the graphics canvas. Dividing that value by two gives the horizontal center.

getHeight() does the same for the vertical center.

This is better than typing fixed coordinates such as 200, 200. A fixed number may work on one canvas size but fail on another.

The 9.7.4 leash codehs answers approach adjusts automatically to the canvas size CodeHS provides. This makes the program more flexible and easier to reuse.

If the canvas changes, you do not need to rewrite the coordinates. The program finds its center each time it starts.

Creating and Positioning the Yellow Ball

The ball is created with this line:

ball = new Circle(BALL_RADIUS);

The value stored in BALL_RADIUS controls its size.

Next, the program places the circle in the center:

ball.setPosition(centerX, centerY);

Then it changes the color:

ball.setColor(Color.yellow);

Finally, this line places the circle on the visible canvas:

add(ball);

Without add(ball), the circle object may exist in the program, but you will not see it.

That small step causes many beginner errors when working through 9.7.4 leash codehs answers and other CodeHS graphics activities. Creating an object and displaying an object are separate steps.

How the Leash Line Is Created

The line starts with this code:

line = new Line(centerX, centerY, centerX, centerY);

A Line needs four coordinate values. The first two values give its starting x and y position. The last two give its ending x and y position.

At first, both points sit in the exact center. So the line has no visible length when the program starts.

That is expected.

As soon as the user moves the mouse, the endpoint changes. The starting point remains fixed in the center.

This is the main visual idea behind 9.7.4 leash codehs answers. The ball can travel around the canvas, but the other end of the line stays attached to its starting location.

After the line is created, add(line); places it on the graphics canvas.

How mouseMoveMethod Controls the Program

This line activates mouse tracking:

mouseMoveMethod(leash);

It tells CodeHS to run the leash function whenever the mouse moves over the canvas.

You do not need to call leash() over and over inside start(). CodeHS handles that part after the mouse event has been registered.

This is known as event-driven programming.

The program waits for something to happen. In this case, the event is mouse movement. When that event happens, a function runs.

For students working on 9.7.4 leash codehs answers, this is worth understanding because the same idea appears in many later projects.

Mouse clicks, keyboard presses, dragging, and movement can all trigger event functions.

What the leash(e) Function Does

The event function receives an event object called e:

function leash(e) {
    ball.setPosition(e.getX(), e.getY());
    line.setEndpoint(e.getX(), e.getY());
}

The e object contains information about the mouse event.

e.getX() gives the current horizontal position of the mouse.

e.getY() gives its current vertical position.

The first line moves the ball to those coordinates:

ball.setPosition(e.getX(), e.getY());

The second line moves the endpoint of the leash:

line.setEndpoint(e.getX(), e.getY());

Both changes happen every time the mouse moves. Because the ball and line endpoint use the same coordinates, they stay connected.

That creates the exact behavior required by 9.7.4 leash codehs answers.

Why setEndpoint Is Important

The line should have one fixed end and one moving end. That is why setEndpoint() works well here.

The line begins in the center of the canvas. Its starting point should remain there for the whole program.

Only its endpoint needs to follow the mouse.

When this runs:

line.setEndpoint(e.getX(), e.getY());

CodeHS changes the second end of the line without moving its starting position.

If you moved both ends, the whole line could travel with the mouse. You would lose the leash effect.

This small difference is one of the most important parts of the 9.7.4 leash codehs answers solution.

Think of the starting point as a hook attached to the center. The endpoint is the part tied to the moving ball.

Common Mistakes That Can Stop the Code

One common mistake is putting ball and line inside start() as local variables. That can keep the mouse event function from accessing them.

Another mistake is forgetting this line:

mouseMoveMethod(leash);

Without it, the program may show the starting ball and line, but nothing will respond when you move the mouse.

Students can also use the wrong method for changing the line. For this task, setEndpoint() is useful because only the moving end should change.

Check spelling as well.

JavaScript is case-sensitive. getX() is not the same as getx(). The same applies to setPosition(), setEndpoint(), and mouseMoveMethod().

If your 9.7.4 leash codehs answers code draws the ball but does not move it, check the event method first. Then make sure ball and line are available to the leash() function.

Understanding the Program Flow Step by Step

The easiest way to understand the program is to divide it into two stages.

First, start() runs once.

It finds the center of the canvas. Then it creates the ball and line. Both begin in the center. It adds them to the canvas and turns on mouse tracking.

Then the program waits.

When the user moves the mouse, CodeHS calls leash(e).

The new mouse coordinates are read from the event object. The ball moves to those coordinates, and the endpoint of the line moves to the same place.

Nothing needs to be recreated.

This is why the 9.7.4 leash codehs answers solution stays short. It does not make a new circle or line every time the pointer moves. It updates the objects that are already on the screen.

That is cleaner and easier to manage.

How to Test Your Leash Program

Run the program and look at the starting screen first. The yellow circle should appear in the center of the canvas.

Next, move the mouse slowly.

The circle should follow your pointer. A line should stretch from the original center point toward the moving circle.

Try moving the pointer into different corners of the canvas.

The fixed end of the line should stay in the same location. The other end should remain attached to the ball.

If those behaviors work, your 9.7.4 leash codehs answers solution is doing what the exercise requires.

You can also change:

var BALL_RADIUS = 30;

Try using 20 or 40. The circle should become smaller or larger while the leash behavior stays the same.

Testing small changes like this is useful because it shows which parts of the program control appearance and which parts control movement.

Bottom Line

The Leash exercise is short, but it introduces several useful JavaScript graphics ideas. You create objects, position them with coordinates, listen for mouse movement, and update existing graphics while the program is running.

The main trick is keeping one end of the line fixed while the ball and the other endpoint follow e.getX() and e.getY().

So if you came here for 9.7.4 leash codehs answers, the code above provides the full solution. But understanding the pattern is more useful than simply copying it.

Create the objects once inside start(). Register the mouse event. Then update the existing objects inside the event function.

The same basic pattern can later be used for drawing tools, simple games, drag-and-drop projects, cursor effects, and other interactive JavaScript graphics programs.

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Technology

Twitch Affiliate Requirements in 2026: What Changed and How to Track Your Progress

Published

4 days ago

November 3, 2026

Apex Backlinks

Twitch Affiliate Requirements in 2026: What Changed and How to Track Your Progress

Twitch lowered the bar for its Affiliate programme in 2026, and many older guides still quote the previous numbers. If you are trying to unlock subscriptions, Bits payouts and the other Affiliate perks, it is worth knowing exactly which goals you need to hit, how Twitch measures them, and how to check your progress without guessing.

The current Affiliate goals

Twitch’s “Path to Affiliate” achievement now asks for four things within the same 30-day window:

25 followers
4 hours of streaming (240 minutes in total)
Streams on 4 different days
An average of 3 viewers on 4 of those days

The old version asked for 50 followers, 500 minutes (about 8 hours) and 7 separate stream days. If a tutorial still lists those figures, it was written before the update.

How the “3 average viewers” rule really works

This is the goal that confuses most new streamers. Twitch does not look at one big average across the whole month. It looks at each stream day separately: a day counts when your average concurrent viewers for that day reaches 3. You need four such days in the last 30 days, and days below 3 simply don’t count. They do not pull the others down.

A few details matter in practice:

Days are counted in GMT. Twitch’s achievement tracker uses GMT without daylight-saving adjustments, while your analytics dashboard shows your local time zone. A late-night stream in the Americas can land on the next day in Twitch’s count.
Chatbots don’t count as viewers.
The average is per day, not per peak. Hitting 10 viewers for five minutes during a raid doesn’t help much if you spend three hours at one viewer.

Because of this, a short, focused stream at a time your community can actually join often does more for the requirement than a long stream in an empty time slot.

Checking your progress with real numbers

The achievement page in your Creator Dashboard shows whether each goal is complete, but it doesn’t explain how close a given day is to the threshold. To plan ahead, you can feed your own stream data into a Twitch average viewers calculator. Enter the length of each stream and the viewers you had, and it shows the average per day and which days already qualify. This is useful when you are deciding whether one more stream this week could complete the goal.

What about Partner?

Partner is the next step and is considerably harder. The current “Path to Partner” achievement asks for 6 streams on 6 unique days with an average of at least 75 viewers, in two consecutive 30-day windows. A broadcast below 75 average viewers simply doesn’t count towards the six. Even when you meet the numbers, Partner is an application: Twitch reviews it, and exceptions are possible for creators who are growing quickly or who bring a large audience from another platform.

A realistic 30-day plan

Pick a fixed schedule. Two or three set days per week, at the same hour, makes it easier for the same people to return. Consistency helps the per-day average more than random long sessions.
Stream for 60 to 90 minutes. Shorter streams make it easier to keep your average above 3 for the whole session.
Bring your existing audience. Friends, Discord members and followers from TikTok or YouTube Shorts are usually your first regular viewers.
Collaborate. Co-streams and raids with streamers of a similar size bring real viewers who already enjoy your category.
Check your days weekly. Once three qualifying days are complete, plan the fourth stream for your strongest time slot.

The zero-viewer start is the hardest part for almost every new channel, and a whole market of growth services has formed around it. On sites like ViewerWorks, for example, streamers can buy Twitch viewers or followers for their broadcasts. Whatever route you choose, the viewers who return week after week are the ones who came for your content.

After you qualify

Twitch sends the Affiliate invitation automatically, but it can take up to 48 hours to appear. Before you accept, make sure your account has two-factor authentication enabled and a verified email address, because both are needed for onboarding and payouts. Once you are in, it helps to estimate what subscriptions and Bits might bring in at your size. A free Twitch earnings calculator gives a quick, realistic picture of subscriptions and Bits before you plan any upgrades to your setup.

For the official wording of each goal, Twitch keeps an up-to-date description on its achievements help page.

Technology

What Kind of Business Can You Launch With a Laser Cutter in Australia?

Published

1 week ago

October 28, 2026

Ghazanfar Ali

A laser cutter lets one person turn timber, acrylic and leather into finished products without a factory. In Australia, that translates into a handful of well-proven micro-business models built around customisation, local style and small-batch work. Here are five that makers and small business owners regularly talk about, followed by guidance on margins, machines and where to sell.

1. Personalised Australiana and Home Décor

Native timber wall signs, nursery name plaques, entry signage and layered wooden artwork are consistent sellers. There is steady local demand for custom timber and for rustic or boho styling in Australian homes, and layered designs are hard to copy by hand, which helps you avoid pure price competition.

Tip: Build a small collection around a theme, such as native florals, coastal towns or nursery names, so customers can buy a matching set.

2. Wedding and Event Décor

Acrylic or timber welcome signs, custom table numbers, place cards and cake toppers sell all year round. Rustic and boho weddings in particular lean on laser-cut details, and couples will pay extra for something made to match their colours and venue.

Tip: Offer ready-to-order packages (signage, table numbers, place cards) so couples can decide quickly and you can batch production.

3. B2B Custom Business Signage

Acrylic company logo signs, QR-code display stands for cafés, and office or door plaques are a good route to repeat customers. Local small and medium businesses tend to have higher average order values than individual buyers, and they come back when they open a new location or change their branding.

Tip: Visit local cafés, clinics, and offices with a sample. A physical piece of work in a business owner’s hand is the best sales pitch you have.

4. Engraved Drinkware and Gifts

Custom tumblers, wine glasses, leather hat patches and cork coasters are popular for markets and online gifting. Unit costs are low, production is quick and margins are strong. One detail to get right: a CO2 laser can’t engrave bare stainless steel directly. Stainless tumblers are usually coated or marked using a fibre laser or a marking compound, so choose products that suit your machine.

5. Custom Prototyping and Short-Run Fabrication

Architectural models, custom packaging inserts, leather goods and small components cut to order fill a niche for independent designers and makers who need a small batch without paying industrial setup fees. This work builds relationships with architects, product designers and artists, which can lead to repeat business.

Choosing the Right Machine for the Business

The laser type should follow the product.

CO2 lasers are the best all-rounder for timber, acrylic, paper, leather and glass etching. They’re the natural choice for wall art and signage.
Fibre lasers are specialised for direct metal engraving, such as jewellery, metal tags and some tumblers, but can’t cut wood.
Diode lasers are an entry-level option for light engraving and softer materials, but they’re generally limited for dense acrylic or glass.

For most of the business ideas above, a CO2 machine covers the widest range of products.

Profitability: What to Expect

Community discussions and local market guides commonly cite gross margins of 60 to 85 per cent on individual custom laser-cut or engraved products. Once you account for platform fees such as Etsy or Shopify, packaging, material waste and marketing, whole businesses typically net around 15 to 30 per cent. Treat these as ballpark figures rather than guarantees. Your own margins will depend on pricing, material costs, how much time each piece takes and how efficiently you batch your work.

Where to Sell

Many Australian makers start on Etsy, Facebook Marketplace, weekend craft and design markets, or a dedicated Shopify store. Markets are useful for testing products and meeting customers face to face. Online stores scale better once you know what sells.

A Machine That Suits Most of These Businesses

If you’re looking for a single machine to cover signage, wedding décor, gifts, and prototypes, the OMTech Polar Lite 55W desktop CO2 laser engraver and cutter is a strong candidate. It’s currently listed at A3,299,orA3,299,orA3,609 with LightBurn included.

Features that matter for the business models above:

Camera positioning. A built-in camera shows your material on screen so you can place designs precisely and reduce waste.
Autofocus and integrated water cooling. Less setup time and no external chiller to find room for.
A 500 × 300 mm working area with pass-through. Large enough for wall signs, wedding signage, and multiple smaller items in one run.
Closed, enclosed design. Safer for home and small studio use, and easier to keep dust and smoke under control with proper extraction.

It works with LightBurn, so you can use standard vector files from design tools. Check the product page for the current specifications and what’s included, and plan for ventilation and a suitable workspace.

Before You Launch

Choose a niche. A focused offer, such as nursery décor or café signage, usually sells better than a general range.
Test your pricing. Include materials, machine time, finishing, packaging, and your own labour.
Check regulations. Registering an ABN and understanding GST and any insurance or council requirements for working from home are worth doing early. For specifics, speak to an accountant or the relevant authority.
Start small. Make a sample range, photograph it well, and test it at a market or on one online channel before scaling.

A Simple First-Month Plan

In week one, choose a niche and design a starter range of five to ten products. In week two, make samples and photograph them in natural light. In week three, list the products online or book a market stall, and approach three local businesses with samples. In week four, review what sold, what people asked for, and what took too long to make, then refine the range. This kind of small, measured launch costs little and tells you more than months of planning.

Final Thoughts

A laser cutter gives you the ability to make products people value precisely because they are personal. Decide whether your strength is homeware, weddings, business signage, gifts, or prototyping; choose a machine that suits your materials, and start with a small range you can make well. Margins in this space can be healthy, but they come from careful pricing, steady marketing, and a product that stands out.

Technology

Sending a Code Is Only One Step

Published

2 weeks ago

October 22, 2026

Apex Backlinks

Planning Phone Verification for Saudi Mobile Numbers

Before a small business adds phone verification, it needs to decide who is responsible for every step behind the screen. A text message can arrive while a customer still cannot finish registering. An accepted code can be followed by an application error. A useful product plan gives each stage an owner and explains what the customer can do if it fails.

Imagine a fictional workshop booking service in Riyadh. Customers choose a session and enter a Saudi mobile number. Before confirming the reservation, the service asks them to enter a one-time password, or OTP, sent by SMS. The business wants evidence of access to the contact number supplied for the booking.

Decide what the code should establish

Successful validation provides evidence that someone could obtain the code sent to that number at that moment. It does not, by itself, establish the applicant’s legal identity, nationality or entitlement to another person’s bookings.

NIST’s digital authentication guidance describes authentication in terms of control of authenticators and classifies telephone-network authentication as restricted within its authentication framework. It also explains that this kind of code entry is not phishing-resistant. A small business should therefore consider what an accepted code will unlock. Checking a booking contact and recovering access to an existing account are different decisions.

For the fictional service, define the immediate outcome narrowly: the number has passed the required check for this booking attempt. The reservation still needs to be saved and confirmed by the application.

Agree where provider responsibilities begin and end

Ask what the selected product and integration actually handle. A delivery service may transmit a code generated elsewhere. A managed verification service may also generate codes, check submissions and enforce some limits. An authentication platform may sit between the application and the SMS provider. The allocation must be explicit.

For the delivery step, Tawked documents SMS OTP delivery to Saudi mobile numbers only, making it one possible component to assess for that number scope. The application team should still establish which responsibilities belong to each part of its chosen setup.

Ask the developer to describe that setup in plain language. Who decides whether a code is valid? Who prevents repeated guesses? What information comes back when sending fails? These answers matter more to planning than a general promise that a service “supports OTP.”

Use a responsibility checklist

For each row, name a person in the business or development team who will confirm the arrangement. Record provider responsibilities from the relevant documentation. Outsourcing a function still leaves someone responsible for checking that it works with the application.

Step	Application responsibility	Provider scope to confirm
Collect the number	Explain the purpose, accept supported formats and allow correction.	Supported destinations and number-format rules.
Request a code	Make an authorized server request tied to the pending action; protect credentials.	Acceptance responses, errors and safe retry behaviour.
Deliver the SMS	Handle reported results and unavailable delivery information.	Delivery arrangements, status meanings and available reports.
Validate the code	Associate the result with the correct number, request and intended action.	Who generates and checks codes, including expiry and single use.
Limit attempts	Address abuse across the application and define recovery.	Limits on sends, resends and incorrect entries; what resets them.
Explain the result	Display accurate messages and available next actions.	Error details and timing information supplied to the application.
Complete the booking	Save the reservation and confirm it only after success.	How a verification result is returned to the application.
Handle support	Own customer enquiries and arrange safe escalation.	Support routes and diagnostic references available to the team.

Keep delivery and completion separate

In the fictional service, an accepted send request means only that the request reached the provider’s documented acceptance stage. Where delivery reports are available, the team must understand their meaning. A reported delivery does not establish that the intended customer read the SMS or submitted its code. Missing delivery information should remain an unknown, rather than being labelled a definite failure.

Code validation is a separate event. The application should advance only on a trusted server decision for the relevant request. An on-screen success message or a delivery status cannot substitute for that decision.

Even after a valid code, saving the reservation can fail. The service should distinguish “number verified” from “booking confirmed” and provide a way to continue without accidentally creating duplicate reservations. This is application behaviour that needs an owner, regardless of who delivered the message.

Set limits that repeated requests cannot bypass

OWASP’s guidance on handling one-time passwords recommends limited validity, single use, strict attempt limits and keeping OTP values out of logs. Ask the developer to show where these controls are enforced, whether in the application’s server or a managed service.

Sending limits and incorrect-code limits address different problems. The first can help control unwanted messages and spending; the second constrains guessing. A fresh code should not create an unlimited new guessing opportunity. NIST’s out-of-band authentication model specifically requires failed-attempt counts to survive the generation of another secret.

Confirm what a resend does to earlier codes and how limits apply across new requests. Choose expiry and retry settings with the developer, considering the action’s risk, the provider’s supported controls and a workable recovery path. There is no need to borrow a countdown or attempt count from an unrelated service.

A visible resend timer should reflect the actual rule enforced by the server. It explains when another request becomes available; it does not enforce that restriction by itself. Code expiry and resend availability should also be treated as separate states.

Give customers an understandable next step

Show the Saudi-number requirement before asking for a code, and let the customer correct the number. If the service offers Arabic and English screens, review the instructions and number display in both languages.

For this fictional application, “Please enter a Saudi mobile number” could explain an unsupported destination. If the server confirms expiry, “This code has expired. Request a new code” gives a next step, provided another request is allowed. When the cause is unknown, “We could not complete verification” is more accurate than blaming the mobile network.

Make the action fit the message. A temporary restriction needs useful waiting information when that is known. A failed booking save needs guidance about the reservation. Avoid wording that unnecessarily reveals whether someone else has an account.

These examples concern application screens. The SMS content available from the selected delivery service is a separate matter and must follow that service’s documented options.

Prepare support before the first customer gets stuck

Give support staff a way to distinguish a sending problem, an unsuccessful code check and a reservation that did not save. Useful diagnostic records can include stage timestamps, a non-secret request reference and an outcome category. Keep OTP values, credentials and unnecessary personal information out of those records; decide who can access them and how long they are needed.

A support enquiry can ask when the problem occurred and what message appeared. Staff should not ask customers to share their OTP or a screenshot containing it. Losing access to a number also needs a defined recovery process; a caller’s request should not become an informal way to bypass verification.

Review accepted requests, delivery outcomes where available, successful validations and confirmed reservations separately. A gap between successful validations and saved reservations is a reason to inspect the application flow. It is not proof of a particular fault.

Before launch, ask the developer and support owner to walk through an incorrect number, a delayed code, repeated resend clicks, an exhausted attempt limit and a booking-save failure. For each situation, agree what the customer sees, what is recorded and who investigates. Launch approval should cover the successful reservation and the response when one of its steps fails.