How long is the length and width?

The perimeter of a rectangle is 80 feet and its length is 12 feet longer than the width. How long is its length and width?

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w = width
w + 12 = length {the length is 12 foot longer than the width}

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

2w + 2(w + 12) = 80 {substituted width, length, and perimeter into perimeter formula}
2w + 2w + 24 = 80 {used distributive property}
4w + 24 = 80 {combined like terms}
4w = 56 {subtracted 24 from each side}
w = 14 {divided each side by 4}

width of rectangle = 14 feet

w + 12 = length of rectangle
= 14 + 12 {substituted 14, in for w, into w + 12}
= 26 {added}

length of rectangle = 26 feet

width = 14 feet
length = 26 feet

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