Two circles with radii r1 = 7 cm and r2 = 3 cm have their centres 20 cm apart. Find the length of the transverse common tangent between them.
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. cm.
Length of transverse common tangent = √[d2 − (r1 + r2)2]
= √[202 − (7 + 3)2]
= √[400 − 100]
= √300 cm