Answer:
Step-by-step explanation:
Itunes : 0.99 per song......let d represent the number of songs
so the expression for this is : 0.99d
Napster : 10 bucks + 0.89 per song
this expression would be : 10 + 0.89d
so if u want to find out when they will be the same, set them equal to each other and solve for d
0.99d = 10 + 0.89d
0.99d - 0.89d = 10
0.10d = 10
d = 10 / 0.10
d = 100.......so 100 songs must be purchased <===
check it...
itunes : napster :
0.99(100) = $ 99 10 + 0.89(100) = 10 + 89 = $ 99
it checks out :)
