ABCD is rectangle. If AD = x + 1, CD= 2x -3 & AC= x+2, find AC.

MY ATTEMPT:

i used pythagorean theorems:

(x +1)^2+ (2x-3)^2 = (x+2)^2

i got the problem from our textbook ... And the answer without solution is at the back of the portion of the book. It says that the answer is 5.

how did they make it to 5, please let me understand.

thanks