Question 971896

I am having trouble and are looking for your assistance. I am subtracting rational expressions and this problem has me tricked.

(x-6)(x+3)/x^2-2x-15 divided by 9(x-5)/x^2-2x-15

with the denominators the same, do I still have to invert the divisor?
<pre>{{{(x - 6)(x + 3)/(x^2 - 2x - 15)}}}{{{"÷"}}}{{{9(x - 5)/(x^2 - 2x - 15)}}}
{{{(x - 6)(x + 3)/(x^2 - 2x - 15)}}}{{{"*"}}}{{{(x^2 - 2x - 15)/9(x - 5)}}} ------ Changing division to multiplication, and inverting divisor
{{{(x - 6)(x + 3)/cross((x^2 - 2x - 15))}}}{{{"*"}}}{{{cross((x^2 - 2x - 15))/9(x - 5)}}} ----- Cancelling trinomial in numerator and denominator
{{{highlight_green((x - 6)(x + 3)/9(x - 5))}}}, or {{{highlight_green((x^2 - 3x - 18)/(9x - 45))}}}