Question

I don't understand this AT ALL! If someone could please help!!!

Answer 1

x^2 = 64 + 64
x^2 = 128
x = 11.31

Answer 2

35
tan(45°) = opposite/adjacent = x/8  ⇒ x = 8 * tan(45°) = 8

36
cos(45°) = adjacent /hypotenuse = 8/x  ⇒ x = 8/cos(45°) = 11.31