Question 978926
First,
{{{9x^2+9x-18=9(x^2+x-2)}}}
{{{9x^2+9x-18=9(x+2)(x-1)}}}
and
{{{3x+6=3(x-2)}}}
So,
{{{(9x^2+9x-18)/(3x+6)=(9(x+2)(x-1))/(3(x+2))}}}
{{{(9x^2+9x-18)/(3x+6)=3(x-1)}}}
So the plot is a straight line.
*[illustration V11.JPG].