Michael J. answered • 07/10/15

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The area of any rectangle is length times width.

Let width = x

Let length = 4x - 1

Area = 60 ft

^{2}Write an equation that uses the area and the variables.

x(4x - 1) = 60

4x

^{2}- x = 60Subtract 60 on both sides of the equation.

4x

^{2}- x - 60 = 0Factor the left side of the equation using FOIL, if possible.

(4x + 15)(x - 4) = 0

Set the factors equal to zero.

4x + 15 = 0 and x - 4 = 0

x = -15/4 and x = 4

We have two solutions. Since we cannot have a negative value for dimensions, we accept the positive value of x.

x = 4

Finally, we substitute this value of x into the dimensions.

width = 4 feet

length = 15 feet

Michael J.

07/10/15