Question
The perimeter of a rectangle is 230 meters, and the
difference between length and breadth is 15 meters. Find the area of the rectangle.Solution
2(L + B) = 230 So L+ B = 115 m ------(1) & L - B = 15 m ------(2) Adding both equations ; So 2L = 130 So L = 65 m & B = 50 m The area of rectangle = L Ă— B = 65 Ă— 50 = 3250 m 2 Alternate Method: (L + B) 2 - (L - B) 2 = 4LB So 1152 - 152 = 4LB So (115 + 15) (115 - 15) = 4LB So LB = 130 ×  100/4 = 3250 m2Â
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