9514 1404 393
Answer:
Step-by-step explanation:
The midpoint formula is useful here. For midpoint M, we have ...
M = (C + D)/2
2M = C + D
2(10, 10) = (15, s) +(t, 3)
(20, 20) = (15+t, s+3)
t = 20 -15 = 5
s = 20 -3 = 17
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Check
(C +D)/2 = ((15, 17) +(5, 3))/2 = (20, 20)/2 = (10, 10) . . . checks OK
