Slope intercept form: y = mx + b
mx = slope
b = y-intercept
We already know the slope is 2/5, so we can write that as 2/5x, or 0.4x
The y-intercept is the value of y when x is equal to 0.
Since we already know what that is, we can fill in the rest of the equation.
Y = 2/5x - 9