The y-intercept is -2 and the slope of the line is 1/2. You can find the slope by using the rise over run method, which is the change in y over the change in x. In the points, x changed by +2, and y by +1, which is 1/2. Substitute that into the formula y=mx + b using one of the points to find the y-intercept, or b. You could use -4 = 1/2(-4) + b, solve for b, and you would get -2.
