Answer:
1st one) y = x - .8
Explanation:
1st one) you start by finding the slope of the line which can be found with y1 - y2/x1 - x2 (in this case: 3.6-2.4/2-1 which = 1/1, or the slope is one). now that we know the slope we need to find the x intercept or the point that the line intercepts the x axis, or when y = 0. We know that that for every one we subtract from x, we subtract one from y (hence the slope 1/1). so when we subtract 1.2 from the y we subtract 1.2 from the x. so the x intercept is -.8. If we put this in y = mx+b we get y = x - .8
2nd one) you do the same thing for the 2nd one then