Tamil Nadu Board of Secondary EducationSSLC (English Medium) Class 9

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 - Mathematics

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Sum

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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Chapter 4: Geometry - Exercise 4.3 [Page 169]

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Tamil Nadu Board Samacheer Kalvi Class 9th Mathematics Answers Guide
Chapter 4 Geometry
Exercise 4.3 | Q 2 | Page 169

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