Question

Quick can anyone help me please, only the ones who know what they are saying lol!!!!!!!!!!!!!!!! This is literally attempt #7 of trying to get this question answered
Determine the value of x. ( no links as answers)

Answer 1

This is a 45°-45°-90° triangle, in which the sides occur in a ratio of 1 to 1 to √2. So x = √2.

If you didn't already know that, you can trigonometry. By definition of cosine,

cos(45°) = 1/x

Then

x = 1/cos(45°) = 1/(1/√2)) = √2