Answer: This is an Algebra problem that requires functions, and possibly some graphing. So let's set up some functions for each and see where they intersect.
Function 1: y=115x,
Function 2: y=90x+50
Let's set these functions equal: 115x=90x+50, so 25x=50, x=2.
After 2 classes the cost will be the same.
Step-by-step explanation:
What I've done here is modeled some functions. The first function is simple. It is just $115 per class hence the function y=115x where x represents classes y represents money.
The second function is y=90x+50 because I'm assuming there is a one time payment for the membership so 50 is just a constant and 90x represents money spent for the class.
Hope this helps!