✔ 最佳答案
Let x, y be the length of the rectangle and width respectively
xy = (x-4)(y+2) ................(1)
x - 4 = y + 2 ...................(2)
From (1),
xy = xy + 2x - 4y - 8
2x - 4y + 8 = 0 .................(3)
From (2),
x - y - 6 = 0 ......................(4)
(3) - (4)*2,
-2y + 4 = 0
y = 2 ..............................(5)
Put (5) into (4),
x = 8
(2) Let x, y be the quantity of 雞 and 兔 respectively
x + y = 43 ........................(1)
2x + 4y = 100 ...................(2)
(2) - (1)*2,
2y = 14
y = 7 ...............................(3)
Put (3) into (1),
x = 36