Model the situation with a linear function and a graph

Question

Giselle pays $220 in advance on her account at the athletic club. Each time she uses the club, $10 is deducted from her account.

Answer 1

Let x = time

Let y = the amount in her account

 

 

When she pays $220, she loses that amount from her account.  She also loses $10 times the time. 

 

 

y = -10x - 220