Considering that the car does 50 miles per gallon, the linear function for the number of gallons of fuel in Jim's fuel tank, n, in terms of the number of miles x that Jim has driven since filling his tank is given by:

<h3>What is a linear function?</h3>
A linear function is modeled by:

In which:
- m is the slope, which is the rate of change, that is, by how much y changes when x changes by 1.
- b is the y-intercept, which is the value of y when x = 0.
In this problem:
- Jim's car holds 14 gallons of fuel, hence
.
- Considering it does 50 miles per gallon, and the amount in the tank will decrease, the slope is
.
Hence, the function is:

You can learn more about linear functions at brainly.com/question/25898120
Answer:
Step-by-step explanation:

To solve for x:
Move all the terms containing "x" to the left side of the equation. Do this by adding x to both sides.
2x+x=3x. The new equation is:
3x-1/2=3
Now, move all terms not containing "x" to the right side of the equation. Do this by adding 1/2 to both sides.
3x=3+1/2 The new equation is:
3x=3 1/2, or 3.5
The final step is to isolate x. To do so, divide each side by 3.
3x/3 = 3 1/2 /3 The new equation is:
x=1 1/6
Their selling price was 2.45 times the price they bought it. If they split the profit evenly and there was two of them, multiply their profit by two and divide that number by 800 to find how much more they sold it for, so they sold it for 245% more than they bought it