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8-48.

Write a polynomial equation for a graph that passes through the point $\left(−1, 60\right)$ and has three $x$-intercepts: $\left(−4, 0\right), \left(1, 0\right)$, and $\left(3, 0\right)$. Homework Help ✎

Start by writing an equation with those intercepts using the Zero Product Property.
$p\left(x\right) = a\left(x + 4\right)\left(x − 1\right)\left(x − 3\right)$

Find the stretch factor by substituting the point.

$(60)=a((-1)+4)((-1)-1)((-1)-3)$
$60=a(3)(-2)(-4)$
$60=a(24)$
$a=\frac{5}{2}$

$y=\frac{5}{2}(x+4)(x-1)(x-3)$