A common area tested in Year 9 entry exams is Pythagoras’ Theorem. However, they’re unlikely to test whether you know the formula or not directly. They’re more likely to test whether you know:

• when to use the formula, and/or
• how to use the formula, and/or
• how to modify the formula,

In order to find the answer. They’ll likely give you situations where it would be up to you to decide on how to go about problem solving, and whether or not Pythagoras’ Theorem would useful in the situation.

Here’s what you need to know:

• Pythagoras’ Theorem helps you to find 1 side if you have the 2 other sides with a formula.
• It applies only to right-angled triangles.

Here's the formula:

Here's how they came up with it:

As with nearly all competitive exam questions, application is tested so let’s see Pythagoras’ Theorem in application.

Example Question/s

Watch video for explanation of the following question/s:

The square box has dimensions as shown. What is the length of the line AH?

A 12√3 B 13√2 C 5√6 D 6√5 E None of these

x = ?

A 6 B 9 C -6 D -16 E None of these

Practice time!

Now, it's your turn to practice.

Click on the button below and start your practice questions. We recommend doing untimed mode first, and then, when you're ready, do timed mode.

Every question has two solutions videos after you complete the question. The first is a quick 60 second video that shows you how our expert answers the question quickly. The second video is a more in-depth 5-steps or less explainer video that shows you the steps to take to answer the question. It's really important that you review the second video because that's where you'll learn additional tips and tricks.

Once you're done with the practice questions, move on to the next checkpoint.

Now, let’s get started on your practice questions.

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