Mathematics
posted by Toni on .
the perimeter of a rectangular field is 140m. If the length is increased by 15m and the breadth is decreased by 5m, the length will become 3 time the breadth. find the length and breadth of the field.

Let L = original field length and W = original field width.
2L + 2W = 140 (perimeter)
L+15 = 3(W5)
L = 3W 15 15 = 3W 30
2(3W 30) + 2W = 140
8W = 140 +60 = 200
W = 25
L = 45
L' = 60 (new dimensions)
W' = 20 "