Question 865798
Starting with:  {{{2(a^2+3(a-2))*3(a^2+3(a+1))}}}

More than one path to simplifying.

{{{2*3(a^2+3a-6)(a^2+3a+3)}}}
{{{6(a^2+3a-6)(a^2+3a+3)}}}


IF you want or must use Distributive property between the two trinomials, you can distribute from the right or from the left, but be consistant.


{{{6(a^2*a^2+3a*a^2-6*a^2+a^2*3a+3a*3a-6*3a+a^2*3+3a*3-18)}}}
Simplify the terms inside the parentheses.
{{{6(a^4+3a^3-6a^2+3a^3+9a^2-18a+3a^2+9a-18)}}}
Cleanest general form including combining like-terms inside parentheses...
{{{6(a^4+6a^3+12a^2-9a-18)}}}
{{{highlight(6a^4+36a^3+72a^2-54a-108)}}}