Question

Square A and rectangle B have the same width. The length of rectangle B is 4 cm greater than its width. The area of rectangle B is 20 cm greater than the area of square A
Set up an equation and solve it to find the area of square A.

-Thanks! :D

Answer 1

Noting that square A is a square, this is what we have:
A = B
A^2 = B x (B + 4) + 20

I can try subbing in A to B
since A = B:

A^2 = A x (A + 4) + 20
20 = A^2 - (A x (A + 4))
20 = A^2 - (A^2 + 4A)
20 = 4A
A = 5

By the way, A is width of square A and B is the width of rectangle B in my solution,