Answer:
Equation: y=(-1/20)x+12.
Slope: -1/20
Y-intercept: (0, 12)
Explanation:
Let x=the number of gallons of gas in Christopher's car.
If we start with 12 gallons, we have the equation: y=(-1/20)x+12.
This equation is already in slope intercept form, so we see that the slope is -1/20, and the y-intercept is (0, 12).
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