SOLUTION: a rectangular plot ground is 10 meters longer than it is wide its area is 20,000 square meters

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Question 862671: a rectangular plot ground is 10 meters longer than it is wide its area is 20,000 square meters

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
a rectangular plot ground is 10 meters longer than it is wide its area is 20,000 square meters
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ok, thx for letting us know.
Do you have a question?
I can solve for length and width, maybe you're too shy to ask for that.
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L*W = 20000
L = W + 10
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(W+10)*W = 20000
W^2 + 10W - 20000 = 0
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B10x%2B-20000+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%2810%29%5E2-4%2A1%2A-20000=80100.

Discriminant d=80100 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-10%2B-sqrt%28+80100+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%2810%29%2Bsqrt%28+80100+%29%29%2F2%5C1+=+136.509716980849
x%5B2%5D+=+%28-%2810%29-sqrt%28+80100+%29%29%2F2%5C1+=+-146.509716980849

Quadratic expression 1x%5E2%2B10x%2B-20000 can be factored:
1x%5E2%2B10x%2B-20000+=+%28x-136.509716980849%29%2A%28x--146.509716980849%29
Again, the answer is: 136.509716980849, -146.509716980849. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B10%2Ax%2B-20000+%29

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W =~ 136.51 meters
L =~ 146.51 meters