Question

jill signed up for a gym membership. her membership costs $35 per month and $12 for every class she takes. if she spent $107 last month how many classes did she take?
unknown -> classes taken
variable -> c
constant -> 35
35 + 12c = 107
-35 -35
12c = 72
12c/12 = 72/12
c = 6

Explanation:

Step1: Define equation for total cost

Let $c$ = number of classes. Total cost: $35 + 12c = 107$

Step2: Isolate variable term

Subtract 35 from both sides:
$12c = 107 - 35$
$12c = 72$

Step3: Solve for $c$

Divide both sides by 12:
$c = \frac{72}{12}$

Answer:

Jill took 6 classes last month.