What is the value of 7 + 5 * 12 - 4

What are “like terms”? why can we only add like terms?

Janie has $3. she earns $1.20 for each chore she does and can do fractions of chores. she wants to earn enough money to buy a cd for $13.50. write an inequality to determine the number of chores, c, janie could do to have enough money to buy the cd.

Ineed i been stuck on this question since yesterday