Answer:
Definition of midpoint
Explanation:
Midpoint formula:
(
+
)/2 (
)/2
Let P' be the midpoint of M'(0, 0) N'(2r, 2s):
(0 + 2r)/2 = r & (0 + 2s)/2 = s
Thus, P' = (r,s)
Let Q' be the midpoint of O'(2t,0) N'(2r, 2s):
(2t+2r)/2=t + r & (0+2s)/2 = s
Thus, Q' = (t + r, s)
Let R' be the midpoint of M' (0, 0) O'(2t,0):
(O + 2t)/2 = t & (0 + 0)/2 = 0
Thus, R' = (t, 0)
Since step 6 of the proof is P' = (r,s), Q' = (t + r, s), R' = (t, 0), which is true when the midpoint formula is applied, the answer is "Definition of midpoint"