If two circles of radii 28 cm and 18 cm touch each other externally, then the length of a common tangent is _________. [Give your answer correct to 2 decimal places.]
Answer & explanation
Correct answer: option 3
Length of direct common tangent = \(\sqrt {d² - ( R - r )² }\)
= \(\sqrt {46² - ( 28 - 18 )² }\)
= \(\sqrt {2116 - 100 }\)
= \(\sqrt {2016 }\)
= 44.899 cm
= 44.90 cm