InterviewSolution
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he area of a reรงtangle gets reduced by 9 square uwnits, if its length is reduced byunits and breadth is increased by 3 units. If we increase the length by 3 units andthe breadth by.2 units, the area increases by 67 square units. Find the dimensionsof the rectangle |
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Answer» Let length of rectangle = x units And width of rectangle = y units Area of rectangle = length * width = x*y The area of a rectangle gets reduced by 9 square units, if its length is reduced by 5 units and breadth is increased by 3 units. So Decrease the length by 5 unit so new length = x - 5 Increase the width by 3 unit so new width = y + 3 New area is reduced by 9 units So new area= xy – 9 Plug the value in formula length * width = area we get (x- 5)(y + 3) = xy- 9 Xy+ 3x – 5y – 15= xy – 9 Subtract xy both side we get 3x - 5y= 6…(1) If we increase the length by 3units and the breadth by 2 units, the area increases by 67 square units. Increase the length by 3 unit so new length = x +3 Increase the width by 2 unit so new width = y + 2 New area is increasedby 67 units So new area= xy + 67 Plug the value in formula length * width = area we get (x+3)(y + 2) = xy+67 Xy+ 2x+3y+6= xy + 67 Subtract xy both side we get 2x+3y = 61…(2)*3 3x - 5y= 6…(1)*2 Cross multiply the coefficient of x we get 6x + 9 y = 183 6x -10y=12 Subtract now we get 19 y = 171 Y = 171/19 = 9 Plug this value of y in equation first we get 2x + 3* 9 = 61 2x= 61 – 27 2x = 34 X = 34/2 = 17 So length is 17 units and width is 9 units |
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