SOLUTION: find the exact solution(s) of each system of equations x^2-y^2=-8 y=2x+1

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Question 840438: find the exact solution(s) of each system of equations
x^2-y^2=-8
y=2x+1
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
find the exact solution(s) of each system of equations
x^2-y^2=-8
y=2x+1
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Substitute for "y" and solve for "x"::
x^2 - (2x+1)^2 = -8
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x^2 - (4x^2 + 4x + 1) = -8
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-3x^2-4x+7 = 0
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-3x^2-7x+3x+7 = 0
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-x(3x+7) + (3x+7) = 0
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(3x+7)(-x+1) = 0
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x = -7/3 or x = 1
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Cheers,
Stan H.
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