An isosceles right triangle has legs that are each 4cm. What is the length of the hypotenuse?

2 Answers
Nov 14, 2015

c = sqrt(32)c=32

Explanation:

We will use the Pythagorean Theorem for this problem.

We know that each leg is 4cm4cm. We can plug those in for aa and bb, to find our hypotenuse, cc.

4^2 + 4^2 = c^242+42=c2
16 + 16 = c^216+16=c2
32 = c^232=c2
c = sqrt(32)c=32

Nov 14, 2015

4sqrt(2)"cm"42cm

Explanation:

By the Pythagorean theorem, the square of the hypotenuse of a right triangle is equal to the sum of the squares of it's legs. That is, for a right triangle with legs aa and bb and hypotenuse cc
a^2 + b^2 = c^2a2+b2=c2

In this case, we have a = b = 4"cm"a=b=4cm, thus

c^2 = (4"cm")^2 + (4"cm")^2 = 32"cm"^2c2=(4cm)2+(4cm)2=32cm2

=> c = sqrt(32"cm"^2) = sqrt(16*2)"cm" = 4sqrt(2)"cm"c=32cm2=162cm=42cm