CircleHard
Question
If the circle x2 + y2 + 2x − 4y − k = 0 is midway between two circles x2 + y2 + 2x − 4y − 4 = 0 and x2 + y2 + 2x − 4y − 20 = 0, then K =
Options
A.8
B.9
C.11
D.12
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