SOLUTION: If a-3b=-1/5 and a+b=15, then what is the value of the polynomial a^2-2ab-3b^2?

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Question 935118: If a-3b=-1/5 and a+b=15, then what is the value of the polynomial a^2-2ab-3b^2?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If a-3b= -1/5
and a+b = 15,
then what is the value of the polynomial a^2-2ab-3b^2?
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Subtract the top equation from the lower equation
and solve for "b"::
4b = 15 1/5
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4b = 76/5
b = 16/5
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Solve for "a"::
a + (16/5) = 75/5
a = 59/5
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Ans:: a^2-2ab-3b^2 = (59/5)^2 - 2(59/5)(16/5)-3(16/5)^2
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Cheers,
Stan H.
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