This is like a linear equation, (y = mx + b) where the cost per month is 25, and our b is the 80 to join in the first place:
y = 20x + 80
You did not share how much was paid for the membership, but if you put the total cost into y, then you can solve for x. Or you can find the total cost by entering in the number of months for x.
Answer:
Equation given
80+25(y)=x
y= Per month(So the amount of months that passed)
x=Total amount
