Question 792387
15m - 3(3m + 4) = 6
15m - 9m -12 = 6
6m -12 + 12 = 6 + 12
6m = 18
6m/6 = 18/6
m = 3

check:
15(3) - 3(3(3) + 4) = 6
45 - 3(9 + 4) = 6
45 - 3(13) = 6
45 - 39 = 6
6 = 6