First, take the equation out of the parentheses. This example shows addition.(if there’s subtraction we’ll need to multiply by negative sign first. ). 6x3-8x-5+3x3+6x+2. Add the like terms. 6x3+3x3=9x3. -8x+6x=-2x. -5+2=-3. The inalienable answer is 9x3-2x-3.