Question

The length of a rectangular photo is 3 cm less than twice its width. If the area of the photo is 104 square cm, Find the length and width of the photo.

Answer 1

A = L * W
A = 104
L = 2W - 3

104 = W(2W - 3)
104 = 2W^2 - 3W
2W^2 - 3W - 104 = 0
(2W + 13)(W - 8) = 0

2W + 13 = 0
2W = -13
W = -13/2 .....this will not work, extraneous solution

W - 8 = 0
W = 8 <== width

L = 2W - 3
L = 2(8) - 3
L = 16 - 3
L = 13 <===length