SOLUTION: how do you graph y= -2x^2+8 and how do you find the vertex and the roots

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Question 455706: how do you graph y= -2x^2+8 and how do you find the vertex and the roots
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
how do you graph y= -2x^2+8 and how do you find the vertex and the roots
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Vertex occurs at x = -b/(2a) = -0/(-4) = 0
f(0) = -2*0^2+8 = 8
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Vertex: (0,8)
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Roots = ?
Solve -2x^2+8 = 0
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-2(x^2-4) = 0
x^2 - 4 = 0
(x-2)(x+2) = 0
x = 2 or x = -2
Those are the roots.
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Cheers,
Stan H.
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