Lora has a gift card from an online music store where all downloads cost the same amount. After downloading 2 songs, the balance on her card was $18.10. After downloading a total of 5 songs, the balance was $15.25.
a) Write an equation in slope-intercept form that represents the amount in dollars remaining on the card as a function of songs downloaded.
b) Identify the slope of the line and tell what the slope represents.
c) Identify the y-intercept of the line and tell what it represents.
d) How many additional songs can Lora download when there is $15.25 left on the card?