How to use the Pythagorean theorem.

The Pythagorean theorem connects the three sides of any right triangle, but it only works if your kid identifies the hypotenuse correctly. Study Butler starts there, with which side is which, before any squaring happens.

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Here is what that looks like.

Study Butler will not print the answer. It points at the next step and lets your kid take it.

An example. The butler answers the question with a question.

legs are 3 and 4, find the last side.

first. is the side you are looking for the longest one, across from the right angle.

yeah, the hypotenuse.

good. so it goes in the c spot. set up a squared plus b squared and keep going.

Where students get stuck.

The same few mistakes come up again and again. Here is where the butler slows things down.

01Putting a leg in the hypotenuse spot

The theorem only works when c is the hypotenuse, and students sometimes plug a leg there. Study Butler always confirms which side is across from the right angle before the equation gets set up.

02Forgetting to take the square root

After adding the squares, the answer is c squared, not c. Kids stop one step early. The butler asks what the equation actually solved for, which surfaces the missing root.

03Using it on non-right triangles

The theorem requires a right angle, and applying it elsewhere gives nonsense. Study Butler has the student check for the right angle first, every time.

Bring the problem they're stuck on.

Type it, say it, or snap a photo. Study Butler walks your kid to the answer one question at a time, so they learn it instead of copying it.

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Questions parents ask.

How do you know which side is the hypotenuse?

It is always the longest side and always sits directly across from the right angle. Study Butler has your kid find it first, because everything else depends on getting that right.

Can you use the theorem to find a leg, not just the hypotenuse?

Yes. Rearrange to a² = c² − b² when the hypotenuse is known and a leg is missing. The butler walks through that rearrangement instead of giving a separate formula to memorize.

Keep going.

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