Answer
$x^{2}-6x-16=0$
Work Step by Step
$x=-2$ or $ x=8\qquad$....get $0$'s on one side.
$x+2=0$ or $ x-8=0\qquad$....Use the principle of zero products (multiplying). The solutions of this equation are $-2$ and $8$.
$(x+2)(x-8)=0\qquad$...use the FOIL method to multiply.
$ x^{2}-8x+2x-16=0\qquad$...combine like terms.
$x^{2}-6x-16=0$
