SOLUTION: solve by the elimination method p=40+q and 7p=-9q+360

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Question 831590: solve by the elimination method p=40+q and 7p=-9q+360
Found 2 solutions by stanbon, Menjax:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve by the elimination method
p=40+q
7p=-9q+360
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Rearrange:
p - q = 40
7p + 9q = 360
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Modify for elimination::
7p - 7q = 7*40
7p + 9q = 360
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Subtract and solve for "q"::
16q = 80
----
q = 5
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Solve for "p"::
p - q = 40
p - 5 = 40
p = 45
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Cheers,
Stan H.
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Answer by Menjax(62) About Me  (Show Source):
You can put this solution on YOUR website!
p=40+q and 7p=-9q+360
so we will times p=40+q by 7,
7p=280+7q
now we have
7p=280+7q
7p=360-9q
we will minus the first equation from the second
we are left with
0=80-16q
16q=80
q=5
put q is 5 into 7p=280+7q to find p
7p = 280 + 35
p=315/7
p=45 and q=5