SOLUTION: The graph of y=ax^2 + bx + C opens up if a > 0 and down if a < 0. Explain why or how that staement is true. What happens as x gets more a more positive or more and more negative?

Question 383243: The graph of y=ax^2 + bx + C opens up if a > 0 and down if a < 0. Explain why or how that staement is true. What happens as x gets more a more positive or more and more negative?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
The graph of y=ax^2 + bx + C opens up if a > 0 and down if a < 0. Explain why or how that staement is true.
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What happens as x gets more a more positive or more and more negative?
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1st: You have to understand that the ax^2 overwhelms the effect of bx+c
as x gets more and more positive or gets more and more negative.
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2nd: So if a>0, y = ax^2 gets higher and higher if x gets more and more
positive OR if x gets more and more negative.
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And if a<0, y = ax^2 gets more and more negative if x gets more and more
positive OR if x gets more and more negative.
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Cheers,
Stan H.

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