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A parabola opening up or down has vertex (4, -1) and passes through (-9, -181/12). Write its equation in vertex form

1 Answer

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Answer:

y = -1/12(x -4)² -1

Explanation:

The vertex form equation for a parabola is ...

y = a(x -h)² +k . . . . . . vertex (h, k); vertical scale factor 'a'

The vertex coordinates are given. To find the scale factor, we substitute the given point.

-181/12 = a(-9 -4)² -1 . . . . . substitute the given values into the equation

-181/12 = 169a -1 . . . . simplify a bit

-169/12 = 169a . . . . add 1

a = -1/12 . . . . . . . multiply by 1/169

The vertex form equation of the parabola is ...

y = -1/12(x -4)² -1

A parabola opening up or down has vertex (4, -1) and passes through (-9, -181/12). Write-example-1
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