### Home > INT2 > Chapter 9 > Lesson 9.1.3 > Problem9-31

9-31.

Write the equation of a function in graphing form for each parabola described below. .

1. A parabola with vertex ($0, -5$) that passes through the point ($-1, 2$).

Use the equation $f(x) = a(x - h)^2 + k$, where ($h, k$) is the vertex.

$f(x) = a(x - 0)^2 - 5$

Use the point ($-1, 2$) to solve for $a$.
$2 = a(-1 - 0)^2 - 5$

$f(x) = 7x^2 - 5$

2. A parabola with vertex ($1, 4$) that passes through the point ($5, -4$).

Follow the same steps detailed in part (a).

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