Question 9872
It's a quadratic equation, so set it equal to zero:
{{{x^2 - 7x - 18 = 0}}}


Factor it:
{{{(x-9)(x+2) = 0}}}


Set each factor = 0, and solve two separate problems:
x-9= 0
x=9


x+2=0
x=-2


R^2 at SCC