Question
Mathematics Question on Sets
If the coordinates of one end of a diameter of the circle x2+y2+4x–8y+5=0, is (2,1), the coordinates of the other end is
A
(A) (–6, –7)
B
(B) (6, 7)
C
(C) (–6, 7)
D
(D) (7, –6)
Answer
(C) (–6, 7)
Explanation
Solution
Explanation:
x2+y2+9x−8y+5=0Centre circle (-2,4)
h+22=−2h=−4−2=−6k+12=4⇒k=7(h,k)→(−6,7)