SOLUTION: Find a quadratic model for the set of values: (-2, -20), (0, -4), (4, -20). Show your work.

Algebra ->  Rational-functions -> SOLUTION: Find a quadratic model for the set of values: (-2, -20), (0, -4), (4, -20). Show your work.       Log On


   



Question 1052699: Find a quadratic model for the set of values: (-2, -20), (0, -4), (4, -20). Show your work.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find a quadratic model for the set of values:
Form:::::::::: ax^2 + bx + c = y
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(-2, -20):::::a(4) - 2b + c = -20
(0, -4)::::::: 0 + 0 + c = -4
(4, -20):::::: a(16) +4b + c = -20
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Note:: c = -4
4a - 2b -4 = -20
16a + 4b -4 = -20
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4a - 2b = -16
16a + 4b = -16
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Modify for elimination::
8a - 4b = -32
16a + 4b = -16
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24a = -48
a = -2
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Solve for "b"::
4a - 2b = -16
4(-2) - 2b = -16
-8 - 2b = -16
2b = 8
b = 4
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Cheers,
Stan H.
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