✔ 最佳答案
4(x - 1) - 5(2 - y) = 0 ...... (1)
26x + 3y + 27 = 0 ...... (2)
(1):
4x - 4 - 10 + 5y = 0
5y = 14 - 4y
y = (14 - 4x)/5 ...... (3)
把(3)代入(2):
26x + 3(14 - 4x)/5 + 27 = 0
兩邊各項分別乘以5:
130x + 3(14 - 4x) + 135 = 0
130x + 42 - 12x + 135 = 0
118x = -177
x = -177/118
x = -3/2
把x值代入(3):
y = [14 - 4(-3/2)]/5
y = 4
答:x = -3/2, y = 4
驗算:
把 x = -3/2 和 y = 4 代入(1):
左方 = 4[(-3/2) - 1] - 5[2 - (4)]
左方 = -10 + 10
左方 = 0
左方 = 右方
把 x = -3/2 和 y = 4 代入(2):
左方 = 26(-3/2) + 3(4) + 27
左方 = -39 + 12 + 27
左方 = 0
左方 = 右方
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