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

Find the length of the chord AC where AB and CD are the two diameters perpendicular to each other of a circle with radius 42 cm and also find ∠OAC and ∠OCA - Mathematics

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Sum

Find the length of the chord AC where AB and CD are the two diameters perpendicular to each other of a circle with radius `4sqrt(2)` cm and also find ∠OAC and ∠OCA

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Solution

Radius of a circle = `4sqrt(2)` cm

In the right ΔAOC,


AC2 = OA2 + OC2

AC2 = `(4sqrt(2))^2 + (4sqrt(2))^2`

= 32 + 32 = 64

AC = `sqrt(64)`

= 8

Length of the chord = 8 cm,

∠OAC = ∠OCA = 45°

Since OAC is an isosceles right angle triangle.

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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 3 | Page 169

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