Equations From Key Points

With your randomly assigned partner, please go to the designated whiteboard, and discuss this question.

A student is trying to fit a quadratic relation to the data shown in this graph. They decide, for better or worse, that the vertex should be placed at $(4,23)$. They know that the vertex form for a quadratic relation, $y=a{\left(x-h\right)}^2+k$, is probably the easiest to start with, and that they want the graph of the quadratic to go through the point $(1,15)$. How can they use this information to find the missing $a$ value for the equation of the quadratic relation?

SOLUTION

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