There are two ways to do this, solve the equation or try all the answers. I'll solve.
[tex]18=(x-2)(x+5)=x^2+3x-10[/tex]
[tex]0=x^2+3x-28[/tex]
[tex]0=(x+7)(x-4)[/tex]
[tex]x=-7\quad \textrm{or} \quad x=4[/tex]
Choice B, [tex]x=-7[/tex]
The other root was not among the choices.
