Geometrymedium · Past Paper
If the sum of the radii of two circles which touch each other externally is 10 cm and the distance between their centers is 10 cm, how many common tangents do they have?
A1
B2
C3
D4
✓ Correct Answer: C — 3
When two circles touch externally, they have 3 common tangents (2 direct, 1 transverse).
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