At a book fair; three books and two magazines cost $7. Two books and five magazines cost $6.50. Find the cost of a book and the cost of a magazine.

3 answers

3b + 2m = 7 ---times 2 ---> 6b + 4m = 14
2b + 5m = 6.5 --times 3--> 6b + 15m = 19.5
subtract them:
11m = 5.5
m = .50

sub into first:
3b + 2(.50) = 7
3b = 6
b = 2

Books cost $2 each and magazines cost 50 cents each

(wow, good prices, old textbook ??)
3b + 2m = 7

2b + 5m = 6.50

solve the system by substitution or elimination

2nd eqn times 3/2...3b + 15/2 m = 9.75

subtracting (to eliminate b)
... 5/2 m = 3.25
correction ... 5/2 m = 2.25