If the length of one side of a square is increased by 4 cm and the length of an adjacent side is decreased by 8 cm, the area of the figure is decreased by 20%. Find the length of each side of the square to the nearest tenth.

Answer 1

(s + 4) (s - 8) = (1 - .20) s^2

s^2 - 4 s - 32 = .8 s^2 ... .2 s^2 - 4 s - 32 = 0 ... s^2 - 20 s - 160 = 0

use the quadratic formula to find s

Answer 2

Thanks!