8 - 3x = 9x - 10 +3x +3x______________ 8 = 12x - 10 +10 +10______________ 18 = 12x __ ___ 12 12 3/2 = x, or x = 1.5
x=2
9x2 + 9x - 10 = (3x - 2)(3x + 5)
Multiply the dimensions. 9x10 is 90 square feet.
type in 9 x 10 then press this button (^) and press 4 and the equals sign