Answer:
102
Step-by-step explanation:
step 1
3x = 15
3 * x = 15 (* means times)
3 x 5 = 15
therefore x = 5
step 2
6(x + 12) expanded = 6 * x + 12
in this case x = 5 so the equation will look like this
6 * (5 + 12)
Step 3
5 + 12 = 17
17 * 6 = 102
therefore the answer is 102
