Bill is purchasing accordion lessons. There is a $20 materials fee and each lesson costs $15. Write an equation for the situation and then determine how many lessons Bill took if his total cost was $125.

The equation is 20 + 15x. Bill took 7 lessons.

Step-by-step explanation:

Let x represent the number of lessons Bill take. Then,

the total cost = materials fee + (each lesson cost). x

Since the materials fee is $20 and each lesson costs $15

The total cost = 20 + 15x

Since Bill's total cost was $125:

→ 125 = 20 + 15x

→ 105 = 15x

→ x = 7