Find the sides of a rectangle whose perimeter is 100m and area 600 sq.m
Answers
Given :
⠀⠀⠀⠀⠀• perimeter of rectangle = 100 m
⠀⠀⠀⠀⠀• area of rectangle = 600 m²
⠀⠀⠀⠀⠀⠀⠀⠀⠀
To Find :
⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀• Sides of reactangle
⠀
Solution :
⠀⠀⠀⠀⠀•Let 'x' be the length of rectangle
⠀⠀⠀⠀and 'y' be the breadth of rectangle.
⟹ Perimeter of rectangle = 2 ( L + B )
⟹ Perimeter of rectangle = 2( x + y )
⟹⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀100 = 2x + 2y⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀...equation(1)
⟹ Area of rectangle = L × B
⟹ Area of rectangle = xy
⟹ ⠀⠀⠀⠀⠀⠀⠀⠀600 = xy
⟹ ⠀⠀⠀⠀⠀⠀⠀⠀600 = x⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀y
⠀⠀⠀
substituting x = 600/y in equation( 1 )
⟹ ⠀⠀⠀⠀2x + 2y = 100
⟹⠀⠀⠀ 2×600 + 2y = 100
⠀⠀⠀⠀⠀⠀⠀y
⟹⠀⠀⠀⠀1200 + 2y² = 100y
⟹⠀⠀⠀⠀y² -50y +600 =0
⟹⠀⠀⠀⠀y² -30y -20y + 600 = 0
⟹⠀⠀⠀⠀y(y -30) -20(y -30) = 0
⟹⠀⠀⠀⠀(y -20) =0 or ( y -30) = 0
⟹⠀⠀⠀⠀y = 20 or y = 30
Substituting (y = 20) in equation (1)
⟹⠀⠀⠀⠀2x + 2y = 100
⟹⠀⠀⠀⠀2x + 40 = 100
⟹⠀⠀⠀⠀x = 30
The sides of the given rectangle are 30 cm and 20 cm.
The sides of the given rectangle is 30cm and 20cm.