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The chord of length 30 cm is drawn at the distance of 8 cm from the centre of the circle. Find the radius of the circle

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#### Solution

Distance AC = `1/2 xx "Length of chord"`

= `1/2 xx 30`

= 15 cm

Distance from the centre = 8 cm

In ΔOAC Radius (OA) = `sqrt("AC"^2 + "OC"^2)`

= `sqrt(15^2 + 8^2)`

= `sqrt(225 + 64)`

= `sqrt(289)`

= 17

Radius of the circle = 17 cm.

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