Question

Use Pythagorean theorem to solve the following problems.

1. leg = 10, leg = 8, find hypotenuse.

2. leg = 10, hypotenuse = 26, find other leg.

Answer 1

The Pythagorean theorem tells you that for legs a and b, and hypotenuse c this relationship holds:
  c² = a² + b²

It can be useful to make a couple of rearrangements of this relation.
  c = √(a² +b²)
  a = √(c² -b²)

1. c = √(10² + 8²) = √164 = 2√41

2. a = √(26² - 10²) = √576 = 24

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It doesn't matter which leg you call "a" and which one you call "b", unless they are specifically marked on the triangle. Then use the marks you are given.