Question

Find the radius of a circle if 2 m is the length of the tangent, 6 m is the distance between the center of the circle the external point.

(a) 7 m

(b) 5 m

(c) √32 m

(d) √38 m

This question was posed to me in my homework.

Asked question is from Number of Tangents from a Point on the Circle topic in division Circles of Mathematics – Class 10

Answer 1

The correct option is (c) √32 m

For explanation I would say: Length of the tangent = \(\sqrt {d^2 – r^2}  \)

2 = \(\sqrt {6^2 – r^2}  \)

r^2 = 6^2 – 2^2

r = \(\sqrt {6^2 – 2^2}  \)

r = \(\sqrt {36 – 4}  \)

r = √32 m