SOLUTION: if the perimeter of a rectangle is expressed by the formula p=2l+2w the side w can be found by the formula ?

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Question 166597: if the perimeter of a rectangle is expressed by the formula p=2l+2w the side w can be found by the formula ?
Found 2 solutions by stanbon, gonzo:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
if the perimeter of a rectangle is expressed by the formula p=2l+2w the side w can be found by the formula ?
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Solve the forula for "w":
P = 2l + 2w
2w = P -2l
w = (P- 2l)/2
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Cheers,
Stan H.

Answer by gonzo(654) About Me  (Show Source):
You can put this solution on YOUR website!
sure.
if you know the other 2 parameters.
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example:
p = 100
l = 5
w = ?????
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formula for perimeter is p = 2*l + 2*w
substitute 100 for p and 5 for l and you get:
100 = 2*5 + 2*w
this becomes
100 = 10 + 2*w
this becomes
90 = 2*w
this becomes
45 = w
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manipulation of the formula for p itself without using any values for any of the variables will show you how.
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the formula for perimeter is p+=+2%2Aw+%2B+2%2Al
subtract 2*l from both sides:
p+-+2%2Al+=+2%2Aw
divide both sides by 2:
%28p+-+2%2Al%29+%2F+2+=+w
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the formula for w as a function of the perimeter and the length is:
w+=+%28%28p-%282%2Al%29%29%2F2%29
it was derived from the formula for perimeter.
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