In two concentric circles the radius of inner is 5 cm a chord of length 24 m of outer circle becomes a tangent to the inner circle. Find the radius of the larger circle.

Asked by Topperlearning User | 27th Jul, 2017, 01:04: PM

Expert Answer:

Let O be the centre of circle and AB be the chord OT is radius of smaller circle

So OTAB since tangent is to radius at its point of contact.

AT = TB = 12 cm

(since perpendicular from centre to the chord bisects it)

So, In triangle OAT,

OA2 = OT2 + AT2

OA2 = 52 + 122

So, OA = 13 cm

Thus, the radius of the larger circle is 13 cm.

 

Answered by  | 27th Jul, 2017, 03:04: PM