Question

HELP!!!!!!!!!!!!!!!!!!!!!!!!

Answer 1

A is the correct answer
(to find diagonal of a square , you can get help from Pythagorean Theorem)

${10}^{2} + 10 {}^{2} = {x}^{2} \\ 100 + 100 = {x}^{2} \\ {x}^{2} = 200 \\ x = \sqrt{200}$




good luck