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The area of a rectangle is 33 ft^2, and the length of the rectangle is 5 ft less than double the width. Find the dimensions of the rectangle.

The area of a rectangle is 33 ft^2, and the length of the rectangle is 5 ft less than-example-1
User Thomas Solti
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1 Answer

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21 votes

Answer:

Length = 6

Width = 5.5

Explanation:

Let's use the variable x to represent the width:

x = width

The question says that the length of the rectangle is "5 ft less than double the width". This length can be represented like this:

2x - 5 = length

To find the area of a rectangle, you multiply the width and length, so we are going to write an equation where we multiply the width and length and set it equal to 33 ft^2, which is the area:

(x)(2x - 5) = 33

Now use basic algebra to solve for x:

2x^2 - 5x = 33

2x^2 - 5x - 33 = 0

2x^2 + 6x - 11x - 33 = 0

(2x^2 + 6x) + (-11x - 33) = 0

2x(x + 3) - 11(x + 3) = 0

(2x - 11) (x + 3) = 0

x = 11/2, -3

x either equals 11/2 or -3. However, remember that x represents the width, and you can't have a negative number for a width, so x = 11/2 or 5.5.

Now plug in 5.5 to the length expression and simplify:

2(5.5) - 5

11 - 5 = 6

The length is 6 and the width is 5.5.

Hope this helps (●'◡'●)

User Yochanan
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