SOLUTION: The width of a rectangle is 7 inches shorter than the length. Find the width of the rectangle if the area is 98 square inches

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Question 404866: The width of a rectangle is 7 inches shorter than the length. Find the width of the rectangle if the area is 98 square inches
Answer by Tatiana_Stebko(1539) About Me  (Show Source):
You can put this solution on YOUR website!
if the width of the rectangle is x inches, then the length is (x+7)
The area of the rectangle is S=W%2AL, W- width, L-length
So the area is x%2A%28x%2B7%29
Equation
x%2A%28x%2B7%29=98
x%5E2%2B7x-98=0
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-7+%2B-+sqrt%28+7%5E2-4%2A1%2A%28-98%29+%29%29%2F%282%2A1%29+
x+=+%28-7+%2B21%29%2F2=7+ or x+=+%28-7+-21%29%2F2=-14%3C0+Extraneous root of the equation
The width is 7 inches, then the length is 7%2B7=14 inches
Answer 7 inches and 14 inches