Two circles of radii 9 cm and 5 cm have their centres 17 cm apart. What is the length of the internal common tangent?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. cm.
Length of internal common tangent = √[d2 − (r1 + r2)2]
= √[172 − (9 + 5)2]
= √[289 − 196]
= √93 cm