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

Rithika buys an LED TV which has a 25 inches screen. If its height is 7 inches, how wide is the screen? Her TV cabinet is 20 inches wide. Will the TV fit into the cabinet? Give reason - Mathematics

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Sum

Rithika buys an LED TV which has a 25 inches screen. If its height is 7 inches, how wide is the screen? Her TV cabinet is 20 inches wide. Will the TV fit into the cabinet? Give reason

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Solution


Take the sides of a right angled triangle ∆ABC as

a = 7 inches

b = 25 inches

c = ?

By Pythagoras theorem,

b2 = a2 + c2

252 = 72 + c2

⇒ c2 = 252 – 72

= 625 – 49 = 576

∴ c2 = 242

⇒ c = 24 inches

∴ Width of TV cabinet is 20 inches which is lesser than the width of the screen ie. 24 inches.

∴ The TV will not fit into the cabinet.

  Is there an error in this question or solution?
Chapter 5: Geometry - Exercise 5.3 [Page 179]

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Tamil Nadu Board Samacheer Kalvi Class 8th Mathematics Answers Guide
Chapter 5 Geometry
Exercise 5.3 | Q 5 | Page 179

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