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Is it possible to design a rectangular park of perimeter 80 m and area 400 m square ? if so, find its length and breadth. |
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Answer» Answer: Hola‼.........❤✌Let length of the rectangular PARK be x m and breadth be y m. According to question, perimeter = 80 m ⇒ 2(l + b) = 80 m ⇒ 2 (x + y) = 80 ⇒ x + y = 40 => y = 40-x i.e, breadth =(40- x) m Now, area = 400 => l×b = 40 => x (40-x) = 400 => x^2 -40x +400 = 0 Here, a = 1, b = –40, c = 400 Now, D = b^2 – 4ac = (-40)^2 – 4(1) (400) = 1600 – 1600 = 0 Since, D=0 So, the GIVEN quadratic equation has equal roots and hence it is possible to design a rectangular park. Now, solving the the quadratic equation x^2 - 40x +400 by quadratic formula, we get x= -b +- √D/ 2a = 40/2 = 20 Hence, length of the rectangular park, x = 20 m & breath = (40-x) = 20 m Hope it's helpful.... ☺ |
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