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The length of a rectangle exceeds it's breadth by 7cm.If the length is decreased by 4 cm and the breadth is increased by 3 cm , the area of new rectangle is same as the area of original rectangle. Find the length and breadth of the original rectangle . |
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Answer» GIVEN :-
TO FIND :-
TO KNOW :- ♠ Area of rectangle = l × b SOLUTION :- Let the breadth of the rectangle be 'x'cm. Length exceeds by 7cm , so , length will be 'x+7'cm. ♦ Area of Original Rectangle = x(x + 7) Now , when the length is decreased by 4cm and breadth is increased by 3cm.
♦ Area of New Rectangle = (x+3)(x+3) Area of Original rectangle is equal to Area of New rectangle. → x(x+7) = (x+3)(x+3) → x² + 7x = x² + 3x + 3x + 9 → x² + 7x = x² + 6x + 9 → x² - x² + 7x - 6x = 9 → x = 9 ★ For Original rectangle,
Hence , length is 16cm and breadth is 9cm for Original rectangle. MORE TO KNOW :- ♠ Area of SQUARE = side² ♠ Area of triangle = (1/2) × b × h ♠ Area of trapezium = [(sum of parallel sides)/2] × h ♠ Area of semi-circle = πr²/2 ♠ Area of parallelogram = l × h ♠ Area of circle = πr² |
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