SOLUTION: the area of a rectangle is 12 square inches. length is 5 more than twice the width. find the length and the width

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Question 846781: the area of a rectangle is 12 square inches. length is 5 more than twice the width. find the length and the width
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
the area of a rectangle is 12 square inches. length is 5 more than twice the width. find the length and the width
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Let x = width

"length is 5 more than twice the width" so 2x+5 is the length

A+=+LW

12+=+%282x%2B5%29%28x%29

%282x%2B5%29%28x%29+=+12

x%282x%2B5%29+=+12

2x%5E2%2B5x+=+12

2x%5E2%2B5x+-+12+=+0

2x%5E2%2B8x+-+3x+-+12+=+0

%282x%5E2%2B8x%29+%2B+%28-3x+-+12%29+=+0

2x%28x%2B4%29+%2B+%28-3x+-+12%29+=+0

2x%28x%2B4%29+-3%28x+%2B+4%29+=+0

%282x-3%29%28x%2B4%29+=+0

2x-3=0 or x%2B4+=+0

2x=3 or x+=+-4

x=3%2F2 or x+=+-4

Toss the negative solution. A negative width makes no sense at all.

So the width is 3%2F2 inches, 1%261%2F2 inches or 1.5 inches

L+=+2x+%2B+5

L+=+2%283%2F2%29+%2B+5

L+=+6%2F2+%2B+5

L+=+3+%2B+5

L+=+8

and the length is 8 inches