Best Buy was having a special in all their tapes and CDs. Jane was able to buy 4 tapes and 3 CDs for $54. Larry bought 6 CDs and 3 tapes for $78. How much did a CD cost on special?
Tapes are $6 and CDs are $10.
c = CDs
Two linear equations with two unknowns:
add them up:
use either of the original equations to solve for c:
So tapes are $6 and CDs are $10.