Question 580403: Find the rule of the quadratic function whose graph passes through the given points (one of which is the vertex). (0,10),(-4,-6),(3,43)?
I need an answer by tonight 2/29/12 please.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Find the rule of the quadratic function whose graph passes through the given points (one of which is the vertex). (0,10),(-4,-6),(3,43)?
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Use each point to create an equation with variable a,b,c.
Solve the system of 3 equation to find a,b,c.
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ax^2 + bx + c = y
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(0,10) gives: 0a + 0b + c = 10
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(-4,6) gives: 16a-4b + c = -6
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(3,43) gives: 9a + 3b + c = 43
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I used the TI-84 Matrix function to get:
a = 1
b = 8
c = 10
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Equation:
y = x^2+8x+10
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Cheers,
Stan H.
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