Answer:
The equation of the graph after translating one unit to the left is;

Step-by-step explanation:
The given equation is 
We note that minimum value of y = 3, where 1/2·x - 2 = 0 and x = 4
Therefore, in moving one unit to the left, we have at the y-intercept where slope of the graph has become inverted (reflection of the real graph) we add one to the x value as follows;

The equation of the graph becomes;
.

Multiply -7 to both sides:
Add 10 to both sides:
Divide 2 to both sides:
Answer: 22 miles per gallon.
Step-by-step explanation: you divide 264 by 12 and you get 22 making it the answer.