Q. 16 A55.0( 2 Votes )

# The centre of two concentric circle is O; a straight line intersects a circle at the points A and B and other circle at the points C and D. If AC = 5 cm. then the length of BD is

A. 2.5 cm

B. 5 cm

C. 10 cm

D. none of these

Answer :

In OAP and OBP

⇒ AP = BP

⇒ OA = OB

⇒ OP = OP

In OCP and ODP

⇒ CP = DP

⇒ CA + AP = BP + DB

⇒ CA = DB + BP-AP

⇒ CA = DB + 0

⇒ CA = DB

So, BD = 5cm

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