Main content

## Geometry (all content)

### Unit 9: Lesson 1

Pythagorean theorem- Intro to the Pythagorean theorem
- Pythagorean theorem example
- Pythagorean theorem intro problems
- Use Pythagorean theorem to find right triangle side lengths
- Use Pythagorean theorem to find isosceles triangle side lengths
- Right triangle side lengths
- Use area of squares to visualize Pythagorean theorem

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# Pythagorean theorem intro problems

CCSS.Math:

Practice using the Pythagorean theorem to solve for missing side lengths on right triangles. Each question is slightly more challenging than the previous.

## Pythagorean theorem

The equation for the Pythagorean theorem is

where a and b are the lengths of the two legs of the triangle, and c is the length of the hypotenuse.

*Want to learn more about the Pythagorean theorem? Check out this video.*

## Want to join the conversation?

- Is there any way on how to do Pythagorean theorem easier im having trouble understanding(39 votes)
- Honestly, it isnt that bad. You will get used to it after practice.(16 votes)

- i wonder how we figured out the pythagoream theorem(23 votes)
- It was proven by Pythagoras. There are several popular proofs (even one done by a former US president [Garfield]). Look up proof of Pythagoras Theorem on YouTube.(5 votes)

- there is so much history in the comments(29 votes)
- this was disrespectful(1 vote)

- So, for the Pythagorean Theorem you do a squared plus b squared equals c squared. Why is a+c=b a thing? I don't get it.(0 votes)
- a+c cannot equal b. This is because c is the hypotenuse. Instead, you could do c²-a²=b².(32 votes)

- Just a quick question, so in a test it could say find the distance of the other 2 sides of the triangle. Can you find out the other 2 sides using the pythagorean theorem or is there another way to find that out?(10 votes)
- There is no way to do it if you are only given 1 side :((6 votes)

- I don't exactly understand how to do this, is there an easier way to do this?(8 votes)
- how can i find the b (the one one the side thats straight)(2 votes)
- you would instead do c^2-a^2=b^2. if you are missing "a" you can also swap those and do c^2 - b^2 = a^2(3 votes)

- A² =2 1/2 inch c²=3 3/8. B²?(6 votes)
- how do

I do this?(4 votes)- Hey Jordan! Here's the process: a² + b² = c². C is the hypotenuse or the longest side of a triangle. B and A are the adjacent and opposite sides. To solve for the unknown side, just substitute the variables with the given numbers, then solve what's necessary, and you will get your answer! here is an example: a = 5, b - x (unknown side), and c = 10. Step 1 (write it out): 5² + x² = 10². Step 2 (solve the squares): 25 x² = 100. Step 3 (necessary solving): 1 - subtaract 25 from both sides: x² = 75. Now you have your answer: x = √75. Hope this helped!(3 votes)

- is there a better way to learn this?(5 votes)