Multiple choice Solve the equation for x : 6x - 27 + 3x = 4 + 9 - x 2 10 6 4 8 Reveal answer Fill a bubble to check yourself D Correct answer Explanation 6x - 27 + 3x = 4 + 9 - x simplifies to 9x - 27 = 13 - x. Adding x to both sides gives 10x - 27 = 13. Adding 27 to both sides gives 10x = 40. x = 4.