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The length of a rectangle is 7 cm less than four times its width. The area of the rectangle is 36 square cm

User IDifferent
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1 Answer

3 votes

Answer:

W = 4 cm and L = 9 cm

Explanation:

I don't see a question, but will assume the problem wants the length(L) and width(W) of the described rectangle.

Let L and W stand for Length and Width.

Area of a rectangle is given by L*W

We are told that L*W = 36 cm^2

We are also told that L = 4W-7 ["length of a rectangle is 7 cm less than four times its width"]

Substituting the second into the first equation:

L*W = 36 cm^2

(4W-7)*W = 36 cm^2 [L = 4W-7]

4W^2-7W - 36 cm^2 = 0

(W-4)(4W+9) = 0

The roots are: 4 and -(9/4)

We'll use the positive value: W = 4

Since L = 4W-7:

L = 4(4)-7

L = 16-7

L = 9 cm

User Alexander Kireyev
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