Question 1121451
for the x-intercept of 3, a factor is (x-3).  For the x-intercept of -6, the factor is (x+6)

the polynomial is f(x)= a(x^2+3x-18)
When x=0, f(x)=-9
-18a=-9
a=(1/2)
f(x)=(1/2)x^2+(3/2)x-9.
{{{graph(300,300,-10,10,-10,10,(1/2)x^2+(3/2)x-9)}}}