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The length of a rectangle is one inch less than twice the width. The perimeter of the rectangle is 40 in. What is the area of the rectangle?

User Awilinsk
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2 Answers

7 votes
40/2=20 one width and length
Width : x cm
Length: 2x-1
Area=width × length=x(2x-1)=2x^2-x


User Matt Healy
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5 votes

Answer:

Area = 91 square inches

Explanation:

Let

L = length of the rectangle in inches

W = width of rectangle in inches

We are given:
The length of a rectangle is one inch less than twice the width

In math terms this is equivalent to:
L = 2W - 1

he perimeter of the rectangle is 40 in.
The perimeter of the rectangle = 2(L+ W)

So in math terms;
2(L + W) = 40

L + W = 40/2

L + W = 20

Since L = 2W - 1 we can substitute for L in terms of W in the above equation:
L + W = 2W - 1 + W = 3W - 1

Equating it to 20 gives
3W - 1 = 20

Add 1 both sides:
3W = 21

W = 7

Which gives

L = 2W - 1 = 2(7) - 1 = 14 - 1 = 13

So L = 13

The area of the rectangle = L x W

= 13 x 7

= 91 square inches

User Monza
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