Start by simplifying the right side:
3m + 12= 2m + (20-2)
3m + 12= 2m + 18
Now get m’s on to one side:
3m + 12= 2m + 18
-2m -2m (Subtract 2m from both sides)
m + 12 = 18
Now get the constants on to the other side:
m + 12 = 18
-12 -12
So:
m= 18-12
m=6
