To find the slope of the line, simply remember the basic equation for the slope intercept.
Y = mx +/- b
Where m = slope or rise/run
b = y intercept.
In this case the slope is a negative value and is -5/2.
40/100 simplify that and you will get .4.
For this function we can find y-intercept.
x=0, y=-2
This graph is on the top, right.
Any number less than or equal to 12