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A rectangle has dimensions x-2 by x+3 andan area of 150. Solve for x.

User Rszaman
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1 Answer

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Let the length of the rectangle be x + 3

Let the width of the rectangle be x - 2

Recall, the area of a rectangle is length * width

Given that area of this rectangle is 150, it means that

(x + 3)(x - 2) = 150

Multiplying each term inside the bracket by the term outside, it becomes

x^2 - 2x + 3x - 6 = 150

x^2 + x - 6 - 150 = 0

x^2 + x - 156 = 0

We would find two terms such that their sum or difference is x and their product is - 156x^2. The terms are 13x and - 12x. Thus, we have

x^2 + 13x - 12x - 156 = =

x(x + 13) - 12(x + 13) = 0

x - 12 = 0 or x + 13 = 0

x = 12 or x = - 13

The value of x cannot be negative because it will make the length and width to be negative. hence,

x = 12

User Xerq
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