Given circles are x2+y2−8x−2y+1=0 and x2+y2+6x+8y=0 Their centres and radius are C1(4,1),r1=16=4 C2(−3,−4),r2=25=5 Now, C1C2=49+25=74 r1−r2=−1,r1+r2=9 Since, r1−r2<C1C2<r1+r2 ∴ Number of common tangents =2
The number of common tangents of the circles given by x2+y2−8x−2y+1=0 and x2+y2+6x+8y=0 is
Held on 26 May 2012 · Verified 6 Jul 2026.
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