A transverse common tangent is drawn to two circles of radius 8.5 cm and 5.5 cm. The centres of the two circles are 18 cm apart. What is the length (in cm) of the tangent?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 8√2.
Length of the tangent = √[182 - (8.5 + 5.5)2]
= √[182 - 142]
= √(324 - 196)
= √128
= 8√2 cm