Given a quadratic equation in the form y = ax2 +bx +c , and four choices of graphs representing that equation, how can you tell which choices could be eliminated right away by looking at the equation and looking at the graphs and doing some minimal calculations and not actually plotting any of the points?

Question

anonymous · Answer

well whether or not a is negative or positive changes whether or not the graph opens upward or downward
negative a
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positive a
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