Question

A service center charges a fee of x dollars for an oil change plus y dollars per quart of oil used. A sample of its sales record is shown.
A table shows the oil tank size in quarts and total cost for two customers. Customer A: Oil tank size, 5 quarts. Total cost, 22.45 dollars. Customer B: Oil tank size, 7 quarts. Total cost, 25.45 dollars.

Write a system of linear equations that represents this situation.

Equation for customer A:
____=22.45$

Equation for customer B:
___=25.45$

Question 2
Find the fee and cost per quart of oil.

$ fee?

$ per quart of oil?

Answer 1

Answer:

• Fee - $14.95, and $1.5 per quart of oil

Step-by-step explanation:

Equation for customer A:

• x + 5y =22.45$

Equation for customer B:

• x + 7y=25.45$

Subtract the first equation from the second and solve for y:

• x + 7y - x - 5y = 25.45 - 22.45
• 2y = 3
• y = 3/2
• y = 1.5

Find x by substituting the value of y:

• x + 5*1.5 = 22.45
• x = 22.45 - 7.5
• x = 14.95