The area of the rectangle is 80 square inches. the length of the rectangle is (2x) inches and width is (x-3). what is the value of X?

A = lw

80 = 2x (x - 3)

80 = 2x (x) - 2x (3)

80 = 2x² - 6x

0 = 2x² - 6x - 80

0 = 2 (x²) - 2 (3x) - 2 (40)

0 = 2 (x² - 3x - 40)

2 2

0 = x² - 3x - 40

0 = x² - 8x + 5x - 40

0 = x (x) - x (8) + 5 (x) - 5 (8)

0 = x (x - 8) + 5 (x + 8)

0 = (x + 5) (x + 8)

0 = x + 5 or 0 = x + 8

- 5 - 5 - 8 - 8

-5 = x or - 8 = x

The values of x are - 5 and - 8.