Question

A rectangular photograph has an area of 65 square inches. If the length of the photo is 3 inches less than twice it's height, find the dimensions of the photo

Answer 1

A = L * H
A = 65
L = 2H - 3

65 = H(2H - 3)
65 = 2H^2 - 3H
-2H^2 + 3H + 65 = 0
(-Hh + 13)(H + 5) = 0

-2H + 13 = 0
-2H = -13
H = -13/-2
H = 6.5 <== height is 6.5 inches

H + 5 = 0
H = -5....this wont work because it is negative

L = 2H - 3
L = 2(6.5) - 3
L = 13 - 3
L = 10 <== length is 10 inches