Find length and width of rectangle

The width of a rectangle is 2 inches less than its length. Find the length and width if the area of the rectangle is 35 inches wide.

x = length
x - 2 = width   {width is 2 less than length} 

Area = length x width 

x(x - 2) = 35   {area is length x width}
x² - 2x = 35   {used distributive property}
x² - 2x - 35 = 0   {subtracted 35 from each side}
(x - 7)(x + 5) = 0   {factored into two binomials}
x - 7 = 0 or x + 5 = 0   {set each factor equal to 0}
x = 7 or x = -5   {solved each equation for x}
x = 7   {length cannot be negative}
x - 2 = 5   {substituted 7, in for x, into x - 2} 

length is 7 in. and width is 5 in.

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