Answer: 32
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Work Shown:
Let
x = number of visits
y = total cost in dollars
The membership costs $18 no matter how many visits you do. If you make x visits, at $1 each, then it costs an additional 1*x = 1x = x dollars. This is added on top of the base membership fee. In total, we know that y = 18+x = x+18
We want the total y to be at most $50. Therefore
. The highest y can get is 50.
Let's replace y with x+18 and isolate x

y is replaced with x+18
subtract 18 from both sides

This tells us that we can make at most 32 visits. In other words, the maximum number of visits is 32.