Geometryhard · Past Paper
If the length of a transverse common tangent to two circles is 8 cm and the radii are 5 cm and 1 cm, find the distance between centers.
A6 cm
B10 cm
Csqrt(65) cm
D12 cm
✓ Correct Answer: B — 10 cm
L = sqrt(d^2 - (r1+r2)^2). 8 = sqrt(d^2 - 6^2) => 64 = d^2 - 36 => d^2 = 100, d = 10 cm.
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