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How do you find the vertex of this parabola? I just plotted the points down on a graphing calculator, but I figure there's a better way.

How do you find the vertex of this parabola? I just plotted the points down on a graphing-example-1
User Andrie
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1 Answer

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When you look at the table, find the y value that has equivalent values on both sides. For example, the y value for the vertex here is 10. After it, the values are 7,-2, and 17, and above it, the values are 7 and -2. This value should also be either the largest y value or smallest y value (depending on whether the parabola opens up or down).
User Isaac Saffold
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