Answer:
comic books = 2
magazines = 15
Step-by-step explanation:
Let c = number of comic books bought
Let m = number of magazines bought
He bought 17 items, so
c + m = 17
Comic books cost $4 each and magazines cost $3 each.
He spent $53 on comic books and magazines, so
4c + 3m = 53
Rearrange c + m = 17 to make m the subject:
m = 17 - c
Substitute m = 17 - c into 4c + 3m = 53 and solve for c:
4c + 3(17 - c) = 53
⇒ 4c + 51 - 3c = 53
⇒ c = 2
Substitute c = 2 into m = 17 - c to and solve for m:
m = 17 - 2 = 15