Answer:
Step-by-step explanation:
6x + 9 = -3x - 21 -6 solve for x
combine similar terms: 6x + 3x = -21 - 6 - 9
simplify: 9x = -36
divide 9 each side x = -4
6x+9=-3x-21-6
6x+3x=-21-6-9
9x=-36
X=-36/9
X=-12
