Answer:(-32,12)
Explanation:
Find the change in x and change in y from point x to point y. In this case it is -20 for x and +11 for y. Since the definition of a midpoint splits the line into 2 equal segments you can use the changes to calculate z. Use the midpoint coordinates and add the changes like this: (-12-20,1+11) and you will get (-32,12) for z.