The area of a square and a rectangle are equal. The length of the rectangle is greater than the side of square by 9 cm and its breadth is less than the side of square by 6 cm. What will be the perimeter of the rectangle?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 78 cm.
| Understanding/Application |
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Let the side of the square be S cm. Length of the rectangle be l cm and breadth of the rectangle be b cm. l = s + 9 cm and b = s - 6 cm ATQ - lb = s2 (s + 9) (s - 6) = s2 s2 - 6s + 9s - 54 = s2 3s = 54 s = 18 |
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l = s + 9 = 18 + 9 = 27 cm b = s - 6 = 18 - 6 = 12 cm Perimeter of rectangle = 2(l + b) = 2(27 + 12) = 2(39) = 78 cm |