Answer
According to the graph the x-intercepts are: $(10,0)$ and $(-2,0)$
Work Step by Step
$f(x)=0$
$x^2-8x-20=0~~$ ($a=1,b=-8,c=-20$):
$x=\frac{-(-8)±\sqrt {(-8)^2-4(1)(-20)}}{2(1)}=\frac{8±\sqrt {144}}{2}=\frac{8±12}{2}$
$x=10$ or $x=-2$
x-intercepts: $(10,0)$ and $(-2,0)$
