306/6 is 51 is you add one to one side and take away the other the six numbers become: 46, 48, 50, 52, 54, 56 as you added one to one side substituting the other you took away from, therefore the smallest would be 46.
What you do here is subtract g from f: x^2 - 5x + 8 - (x^2 -4); x^2 - 5x + 8 - x^2 + 4; Rearranging gives you x^2 - x^2 - 5x + 8 + 4 which is, simplified, -5x + 12
Answer:
Coordinates of the midpoint are (-5.5, 5)