What angle is congruent to C?

Will give brainliest what is the value of x? enter your answer in the box.

When solving this problem: 3025/5.5 = a/90.75 you get 49912.5 which would be the length of one of the sides of a square when the area is only 90.75 inches. is that answer correct, why, and how is it possible?

I’m really confused and need your assist me with this question i’ve never been taught