Y + 15 - 8 = 22
What does y equal?

15

Step-by-step explanation:

y +15-8 =22

y +15 =22 +8

y +15 =30

y =30-15

y=15

Since y represents the total fee and x represents the number of days late, our equation would be y = 0.30x.

Now since x represents a number of days, it should be a positive integer. This is because of course, we don't count a negative number of days late, and the library doesn't charge for late half-days, for example.

From the given points, only (8 , 2.40) has a positive integer for x. We can check that 2.40 = (0.30) x 8, so it also fits the equation.

Hope this helps!