Answer:
-4/17
Explanation:
You want the slope of the line described by the equation 20x +85y = 120.
Slope
Putting the equation in slope-intercept form by solving for y gives ...
20x +85y = 120
85y = -20x +120
y = -20/85x +120/85
y = -4/17x +24/17
The slope is the coefficient of x: -4/17.
The rate of change is -4/17.