What is the midpoint of the segment shown below? (-2, 3) (10, 3)

The two points are (-2,3) and (10,3)

The x coordinates of each point are -2 and 10. Add them up and we get -2+10 = 8. Cut this in half to get 8/2 = 4
This is the x coordinate of the midpoint

Do the same for the y coordinates. 
Add them up: 3+3 = 6. 
Divide by 2: 6/2 = 3
This is the y coordinate of the midpoint

The midpoint is therefore (4,3)