SOLUTION: Can you please help me solve this equation i have been trying for the past 7 hours and it just dosent make any sense: A rectangle is initially 6cm wide and 12cm long. If a st

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Question 80698: Can you please help me solve this equation i have been trying for the past 7 hours and it just dosent make any sense:
A rectangle is initially 6cm wide and 12cm long. If a strip of uniform width is added to the outside of each of the four sides, the resulting area is 160 square cm. Determine the width of the strip?

Found 2 solutions by stanbon, josmiceli:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A rectangle is initially 6cm wide and 12cm long. If a strip of uniform width is added to the outside of each of the four sides, the resulting area is 160 square cm. Determine the width of the strip?
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Draw the picture of the rectangle.
Draw the stip bordering the rectangle but outside it.
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Let the width of the stip be "x" cm.
Area of the resulting rectangle including the border is:
(6+2x)(12+2x)= 160 sq cm.
4(3+x)(6+x)=160
[18+9x+x^2)= 40
x^2+9x-22=0
(x+11)(x-2)=0
Positive answer: x=2 cm
This is the width of the border.
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Checking: (6+2*2)(12+2*2)= 10*16=160
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Cheers,
Stan H.

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Call the width of the strip x
The new length of the rectangle will be 12+%2B+2x because
there's a strip on both sides
The new width will be 6%2B2x
%286%2B2x%29%2812%2B2x%29+=+160
2%2A%283%2Bx%29%2A2%286%2Bx%29+=+160
4%2A%2818+%2B+9x+%2B+x%5E2%29+=+160
x%5E2+%2B+9x+%2B+18+=+40
x%5E2+%2B+9x+-+22+=+0
%28x-2%29%28x%2B11%29+=+0
Eith x+=+-11 or x+=+2 Negative x is not allowed, so
x+=+2 answer
check
%286%2B2x%29%2812%2B2x%29+=+160
%286%2B2%2A2%29%2812%2B2%2A2%29+=+160
10%2A16+=+160
OK