What is this answer to this question

Flashback to semester a. are triangles pqr and stu congruent? what is the congruency that proves they are congruent? what is the perimeter of triangle pqr? show your work.

If f(x)=-x^2+6x-1 and g(x)=3x^2-4x-1,find(f+g)(x)

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?