Perimeter of a rectangle

The length of a rectangle is three less than twice the width. If the perimeter is 24 inches, what are the length and width of the rectangle? 

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x = width
2x - 3 = length   {length is 3 less than twice width}

Perimeter of a rectangle is 2(width) + 2(length)

2x + 2(2x - 3) = 24   {perimeter is 2(width) + 2(length)}
2x + 4x - 6 = 24   {used distributive property}
6x - 6 = 24   {combined like terms}
6x = 30   {added 6 to both sides}
x = 5   {divided both sides by 6}
2x - 3 = 7   {substituted 5, in for x, into 2x - 3}

width = 5 inches
length = 7 inches 

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