Chapter 8 - Graphing Quadratic Functions - 8.1 - Graphing f(x) = ax^2 - Exercises - Page 424: 25

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If parabola opens up and its vertex is $(-4,2)$, then $2$ is the lowest value of the function, but if it also goes through the point $(6,-3)$, it also gets the value $-3$ which is less than $2$ and it is not possible.