Answer:
[tex]y=-\frac{1}{20} x + 20[/tex]
Step-by-step explanation:
The slope equation is always [tex]\frac{rise}{run}[/tex]. In this case, the gallons went down by 1- so we can call the rise -1. When it went down by 1, the miles went up by 20- so we can call the run 20. This gives us a fraction (the "m" value) to put in the slope equation [tex]y=mx+b[/tex]. To find the y intercept (the "b" value), you find out what y is when x = 0, which is given in the chart: 20.
