✔ 最佳答案
1)
2x -11y +4 =0 ____(1)
3x - 4y +1 =0 _____(2)
(1)式乘3
6x -33y +12 =0 ____(3)
(2)式乘2
3x - 4y +1 =0
6x – 8y + 2 = 0 _____(4)
(4)式減(3)式
25y – 10 = 0
25y = 10
y = 2/5
結果代入(2)式
3x – 4(2/5) + 1 = 0
3x – 3/5 = 0
x = 1/5
2)
8x - 3y +4 = 0 ____(1)
-5x +7y – 2.5=0 ____(2)
(1)式乘5
40x – 15y + 20 = 0 ____(3)
(2)式乘8
-40x + 56y – 20 = 0 ____(4)
(3)式加(4)式
41y = 0
y = 0
代入(1)式
8x – 3(0) + 4 = 0
x = -1/2