Yo have to find the distance between point L and point M. First, you have to do the x values. 1 - -3 = 4. Then, you subtract the y values. -2 - 4 = -6. Next, you add the found numbers to the x and y of the midpoint (m). Leaving 1 +4=5 and -2 + -6 = -8.
(5,-8)