Find the x-intercepts.
-$$f ( x ) = - x ^ { 2 } + 17 x - 72$$
A) $x$-intercepts $( - 8,0 )$ and $( - 9,0 )$
B) $x$-intercepts $( 8,0 )$ and $( 9,0 )$
C) No $x$-intercepts
D) $x$-intercepts $( 8,0 )$ and $( - 9,0 )$

Question

Quizplus · Accepted Answer

To find the x-intercepts, we need to set $f(x) = 0$ and solve for $x$. 
$$0 = -x^2 + 17x - 72$$
Factoring or using the quadratic formula gives us
$$0 = -(x-9)(x-8)$$
So the x-intercepts are at $(8,0)$ and $(9,0)$.

Find the X-Intercepts f(x)=−x2+17x−72f ( x ) = - x ^ { 2 } + 17 x - 72f(x)=−x2+17x−72

Find the X-Intercepts $f ( x ) = - x ^ { 2 } + 17 x - 72$