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The Length of a Rectangle is Twice the Side of a Square and Its Width is 6 Cm Greater than the Side of the Square. If Area of the Rectangle is Three Times the Area of the Square; - Mathematics

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Question

The length of a rectangle is twice the side of a square and its width is 6 cm greater than the side of the square. If the area of the rectangle is three times the area of the square; find the dimensions of each.

Sum
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Solution

Let a be the length of the sides of the square.

According to the question,
2a x ( a + 6 ) = 3a2
2a2 + 12a = 3a2
a = 12

Hence sides of the square are 12 cm each and
Length of the rectangle = 2a = 24 cm.
Width of the rectangle = a + 6 = 18 cm.

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Chapter 20: Area and Perimeter of Plane Figures - Exercise 20 (B) [Page 256]

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Selina Concise Mathematics [English] Class 9 ICSE
Chapter 20 Area and Perimeter of Plane Figures
Exercise 20 (B) | Q 30 | Page 256

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