Question 11375
What equation?  I don't see the = sign.

Do you mean...Simplify this expression?  That can be done.

{{{(3x^4-4x^2-18)-(2x^4+3x^3+6)}}} Remove the 2nd set of parentheses and change the sign of evey term inside.

{{{(3x^4-4x^2-18)-2x^4-3x^3-6}}} Remove the 1st set of parentheses and collect like-terms.

{{{(3x^4-2x^4)-3x^3-4x^2- 24}}} Simplify.

{{{x^4-3x^3-4x^2-24}}} Done!