SOLUTION: Without graphing, determine the vertex of the given parabola and state whether it opens upward or downward. y = -3x2 - 18x - 32

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: Without graphing, determine the vertex of the given parabola and state whether it opens upward or downward. y = -3x2 - 18x - 32      Log On


   

Question 535254: Without graphing, determine the vertex of the given parabola and state whether it opens upward or downward.
y = -3x2 - 18x - 32
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Without graphing, determine the vertex of the given parabola and state whether it opens upward or downward.
y = -3x2 - 18x - 32
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The negative on the highest power term
assures the parabola opens downward.
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The vertex occurs where x = -b/(2a) = 18/(2*-3) = -3
f(-3) = -3(-3)^2 - 18(-3) - 32
f(-3) = -27 + 54 - 32
f(-3) = -5
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Vertex at (-3,-5)
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Cheers,
Stan H.
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