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In Fig., chords AB and CD of the circle intersect at O. AO = 5 cm, BO = 3 cm and CO = 2.5 cm. Determine the length of DO.

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#### Solution

Clearly, Chords AB and CD intersect at O.

∴ OA x OB = OC x OD

⇒ 5 x 3 = 2.5 x OD

⇒ OD = `(( 5 xx 3)/2.5)` = 6 cm.

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