Tamil Nadu Board of Secondary EducationSSLC (English Medium) (5 to 8) Class 8

Find the unknown side in the following triangles - Mathematics

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Sum

Find the unknown side in the following triangles

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Solution

From ∆ABC, by Pythagoras theorem

BC2 = AB2 + AC2

Take AB2 + AC2 

= 92 + 402

= 81 + 1600

= 1681

BC2 = AB2 + AC2 

= 1681

= 412

BC2 = 412

⇒ BC = 41

∴ x = 41

  Is there an error in this question or solution?
Chapter 5: Geometry - Exercise 5.2 [Page 178]

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Tamil Nadu Board Samacheer Kalvi Class 8th Mathematics Answers Guide
Chapter 5 Geometry
Exercise 5.2 | Q 4. (i) | Page 178

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