Question

A photograph has a length that is 3
inches longer than its width, x. So its area is given by the expression x(x+3)
square inches. If the area of the photograph is 70
square inches, what is the length of the photograph?

The length of the photograph is blank inches.

Answer 1

Set up the equation x(x + 3) = 70 → x^2 + 3x - 70 = 0.
Factor: (x + 10)(x - 7) = 0, so x = 7 (discard x = −10).
Length = x + 3 = 7 + 3 = 10 inches.