A square poster has sides measuring 2 feet less than the signs of a square sign. If the difference between the two areas is 12 square feet, find the lengths of the sides of the poster and the sign.

Question

anonymous · Answer

If the square sign has a side of "x" then
The square poster has sides of "x-2"
 x^2 - (x-2)^2= 12        
x^2 - (x^2 - 4x + 4)  = 12
x^2 - x^2 + 4x - 4 = 12
4x - 4 = 12
4x = 16
x = 4
Square sign is 4 x 4
Square poster is 2 x 2

16 - 4 = 12