Answer :
Answer: it would take 12 hours before you pay the same amount for both companies.
Step-by-step explanation:
Let x represent the number of hours that you spend at either company A or company B
Let y represent the total amount paid for x hours at company A
Let z represent the total amount paid for x hours at company B
Company A charges $120 for parts and $50 per hour. This means that the total amount for x hours would be
y = 50x + 120
Company B charges $60 for parts and $65 per hour. This means that the total amount for x hours would be
z = 65x + 60
To determine the number of hours before the amount for both companies becomes the same, we would equate y to z. It becomes
50x + 120 = 65x + 60
65x - 50x = 120 - 60
5x = 60
x = 12