Khan/khan-exercises — Issue #13480: Pythagorean theorem 1 - Pythagorean Theorem
Author: KhanBugz
Created: 2012-02-09 16:48:20+00:00
State: open
Labels: safari, snowleo, wrong-or-unclear

Pythagorean theorem 1
In the right triangle shown, AC=4 and AB=7. What is BC?

ACB4?7
We know a2+b2=c2.

We want to find a; let b=4 and c=7.

So a2=c2−b2=72−42=33.

Then, a=33−−√.

Answer
√

I typed square root 33 and was told answer is wrong.

[pythagorean_theorem_1.html?seed=181&problem=find-a-leg](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/pythagorean_theorem_1.html?seed=181&problem=find-a-leg&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/pythagorean_theorem_1.html?seed=181&problem=find-a-leg&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5Bnull%2C33%5D%22%2C41%5D%2C%5B%22hint-activity%22%2C%220%22%2C2%5D%2C%5B%22hint-activity%22%2C%220%22%2C2%5D%2C%5B%22hint-activity%22%2C%220%22%2C3%5D%2C%5B%22hint-activity%22%2C%220%22%2C3%5D%5D)

[[null,33]]

Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_6_4; en-us) AppleWebKit/533.18.1 (KHTML, like Gecko) Version/5.0.2 Safari/533.18.5

MathJax is loaded, ready, queue length: 0