First, you wanna subtract 9 from both sides which gives you -3. Next, you’ll have to divide both sides by 3 but first you gotta cancel out 3x ÷ 3 and divide -3 by 3 which then gives you the answer to x which is -1.
3x + 9 = 6
3x + 9 - 9 = 6 - 9
3x = -3
3x ÷ 3 = -3 ÷ 3
x = -1