Word problem involving perimeter

The perimeter of a rectangle is 74 inches. Find the dimensions if the length is 7 inches greater than twice the width.

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x = width
2x + 7 = length   {the length is 7 greater than the twice the width}

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

2x + 2(2x + 7) = 74   {perimeter is 2(width) + 2(length)}
2x + 4x + 14 = 74   {used distributive property}
6x + 14 = 74   {combined like terms}
6x = 60   {subtracted 14 from each side}
x = 10   {divided each side by 6}
2x + 7 = 27   {substituted 10, in for x, into 2x + 7}

width is 10 inches
length is 27 inches

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