Answer:
$1230
Step-by-step explanation:
First of all, your initial equation is wrong. It should be:
cost = 30m + 150
To find how much 3 years will cost you have to first find how many months are in 3 years:
12 • 3 = 36
Then substitute 36 for m in the equation:
cost = 30(36) + 150
Then solve:
C = 30(36) + 150
C = 1080 + 150
C = 1230