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The Diagonal of a Square is 12 Cm Long; Find Its Area and Length of One Side.

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Question

The diagonal of a square is 12 cm long; find its area and length of one side.

Sum
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Solution

Let side of square = a cm
diagonal = 12 cm
By Pythagoras Theorem, a2 + a2 = (12)2
2a2 = 144
a2 = 72
Area of square = a2 = 72 cm2
a2 = 72
a = `sqrt(72)` = 8.48 cm

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Chapter 22: Area of a Trapezium and a Polygon - Exercise 20 (B) [Page 227]

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Selina Concise Mathematics [English] Class 8 ICSE
Chapter 22 Area of a Trapezium and a Polygon
Exercise 20 (B) | Q 7 | Page 227

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