SOLUTION: The perimeter of a rectangle is 90 cm. The length is 15 cm more than four times the width. What is the dimensions of the rectangle?

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Question 412827: The perimeter of a rectangle is 90 cm. The length is 15 cm more than four times the width. What is the dimensions of the rectangle?
Answer by algebrahouse.com(1659) About Me  (Show Source):
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"The perimeter of a rectangle is 90 cm. The length is 15 cm more than four times the width. What is the dimensions of the rectangle?"

x = width
4x + 15 = length

2x + 2(4x + 15) = 90 {perimeter equals (2 x width) plus (2 x length)}
2x + 8x + 30 = 90 {used distributive property}
10x + 30 = 90 {combined like terms}
10x = 60 {subtracted 30 from both sides}
x = 6 {divided both sides by 10}
4x + 15 = 39 {substituted 6, in for x, into 4x + 15}

width = 6cm
length = 39cm
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