First, solve for the slope. This can be found by looking at the y and x intercepts. At x = 0, y = 1.5. At x = 2, y = 0.
Slope is defined as Δy/Δx, or the change in y over the change in x. This means that in order to calculate the slope, you must find the difference between the values of y and divide it by the difference in the values of x for the two points to determine the slope between them.
(0 - 1.5)/(2-0) = (-1.5)/2 = -0.75 or -3/4
Now that you have the slope, we can write the equation in slope intercept form, y = mx + b, where m is the slope we calculated and b is the y intercept, 1.5.