How do you find the length of the legs when only given the hypotenuse with an isosceles right triangle?

The side length ratios of an isosceles right triangle are 1-1-. So, the length of a leg would be equal to the length of the hypotenuse divided by the square root of 2.

Using pythagorean theorem (c is the hypotenuse, a and b are the legs)
c²=a²+b²
If the triangle is isosceles, two side lengths must be equal. In the case of a right triangle, the legs must be equal in length. So, b=a.
c²=a²+a²
c²=2a²
a²=c²/2
a=c/
a≈c/1.414

Ithink the answer is b