Question 1027185

Could someone please help me with this problem multiplying rational expressions?  I am supposed to describe and correct the error, but I don't know how to show you what is cancelled out.  So, if someone could just please show me how to work the problem, I can figure out the error.  The problem is: 
15x^2-9x-6/3x^2-3x-6 *6x^2-6x-12/2x^2+2x-4.
Thanks for your time!
<pre>USE PARENTHESES! Why can't you use parentheses?
Assuming it's: {{{((15x^2 - 9x - 6)/(3x^2 - 3x - 6)) * ((6x^2 - 6x - 12)/(2x^2 + 2x - 4))}}}
{{{3(5x^2 - 3x - 2)/3(x^2 - x - 2)}}} * {{{6(x^2 - x - 2)/2(x^2 + x - 2)}}} ----- Factoring out GCFs
{{{cross(3)(5x^2 - 3x - 2)/cross(3)(x^2 - x - 2)}}} * {{{3cross(6)(x^2 - x - 2)/cross(2)(x^2 + x - 2)}}} ---- Cancelling GCFs
{{{(5x^2 - 3x - 2)/(x^2 - x - 2)}}} * {{{3(x^2 - x - 2)/(x^2 + x - 2)}}}
{{{(5x + 2)(x - 1)/(x^2 - x - 2)}}} * {{{3(x^2 - x - 2)/(x - 1)(x + 2)}}}
{{{(5x + 2)cross((x - 1))/cross((x^2 - x - 2))}}} * {{{3cross((x^2 - x - 2))/cross((x - 1))(x + 2)}}}
{{{highlight_green(matrix(1,3, 3(5x + 2)/(x + 2), or, (15x + 6)/(x + 2)))}}}