A local recreation center offers a yearly membership for $265. The center offers aerobics classes for an additional $5 per class.

a. Write an equation that represents the total cost of the membership. (Suppose that y is the total cost and x the the number of classes)

b. Carly spent $500 one year. How many aerobics classes did she take?

a. y = 265 + 5x

b. 500 = 265 + 5x

   5x = 500 - 265

   5x = 235

   x = 235/5

   x = 47

She took 47 aerobic classes.    

Step-by-step explanation:

Total Cost is yearly cost + 5 into however many aerobic classes you take.

Find the number of classes by substituting values in the equation.

341

step-by-step explanation:

all you have to do is 9x31 (which equals 279) and then 20x31 (which equals 620). then you have to subtract. 620-279=341.