Question

Which is a true statement about an isosceles right triangle?

Answer 1

Let $l$ be the length of a leg. Using the pythagorean theorem, the hypotenuse is

$h = \sqrt{l^2+l^2}=\sqrt{2l^2}=l\sqrt{2}$

So, the hypotenuse is $\sqrt{2}$ times as long as either leg.