Question

The legs of an isosceles right triangle are 20 cm long. Find the length of the hypotenuse. Round to the nearest tenth if necessary

Answer 1

Use the Pythagorean theorem:
$(leg)^2+(leg)^2=(hypotenuse)^2 \\ 20^2+20^2=x^2 \\ 400+400=x^2 \\ x^2=800 \\ x=\sqrt{800} \\ x=28.28... \\ x \approx 28.3$

The length of the hypotenus is approximately 28.3 cm.