Question

Two concentric circles are of radii 5 cm and 3 cm. Find the length of the chord of the
larger circle which touches the smaller circle.
8. A quadrilateral ABCD is du
circle (see Fig 10.12). Prove that​

Answer 1

MATHS

Two concentric circles are of radii 5 cm and 3 cm. Find the length of the chord of the larger circle which touches the smaller circle.

ANSWER

Let O be the centre of the concentric circle of radii 5 cm and 3 cm respectively. Let AB be a chord of the larger circle touching the smaller circle at P.

Then

AP=PB and OP⊥AB

Applying Pythagoras theorem in △OPA, we have

OA2 =OP 2 +AP 2

⇒25=9+AP 2

⇒AP 2=16⇒AP=4 cm

∴AB=2AP=8 cm