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The length of rectangle is 3 more than twice the width

User Fulvio
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Answer:

The length of a rectangle is 3” more than twice the width. The area of the rectangle is 150 in^2. Find the dimensions of the rectangle.

The length of a rectangle is 3” more than twice the width. The area of the rectangle is 150 in^2. Find the dimensions of the rectangle.

Wyzant

MATH QUADRATIC FORMULA

Kyle C. asked • 05/05/16

The length of a rectangle is 3” more than twice the width. The area of the rectangle is 150 in^2. Find the dimensions of the rectangle.

The length of a rectangle is 3” more than twice the width. The area of the rectangle is 150 in^2. Find the dimensions of the rectangle.

ANSWER

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We know that Area = Length x Width

in this case, L = 2W + 3 and A = 150in2

so, 150in2 = W x (2w + 3)

150in2 = 2W2 + 3W

rearranging, 2W2 + 3W - 150in2 = 0

we need to use the quadratic formula to solve this equation

that formula is [-b±(√b2 -4ac)]/2a

a = 2, b = 3, c = -150

inserting those values, we get [-3±(√32 -4•2•-150)]/2•2

which becomes (-3±√1209)/4

we get (-3 ± 34.771)/4

we can discard the negative value, because no length can be negative

so, W ≅ 7.942 inches

then L = 2W + 3 ≅ 18.886 inches

Proof: 7.942in x 18.886in ≅ 149.99

HOPE IT'S HELPFUL

THANK YOU

User Shripal
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