2X=3Y,4x-5y=2 -6x+5y=3,3x=4y 2x+3y=5,3x=y-9 3x=1-y,3x=2y-5
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2X=3Y,4x-5y=2 -6x+5y=3,3x=4y 2x+3y=5,3x=y-9 3x=1-y,3x=2y-5
![2X=3Y,4x-5y=2 -6x+5y=3,3x=4y 2x+3y=5,3x=y-9 3x=1-y,3x=2y-5](/uploads/image/z/1777756-4-6.jpg?t=2X%3D3Y%2C4x-5y%3D2+-6x%2B5y%3D3%2C3x%3D4y+2x%2B3y%3D5%2C3x%3Dy-9+3x%3D1-y%2C3x%3D2y-5)
2X=3Y (1)
4x-5y=2 (2)
(1)*2-(2)得
5y=6y-2
y=2
将也代入(1)
2x=3*2
x=3
-6x+5y=3 (1)
3x=4y (2)
由(2)得
x=4/3y (3)
将(3)代入(1)得
-6*(4/3y)+5y=3
y=-1
将y=-1代入(3)得
x=4/3*(-1)
x=-4/3
2x+3y=5 (1)
3x=y-9 (2)
由(2)得
y=3x+9 (3)
将(3)代入(1)得
2x+3(3x+9)=5
11x=-22
x=-2
将x=-2代入(3)得
y=3*(-2)+9
y=3
3x=1-y (1)
3x=2y-5 (2)
由(1)得
y=1-3x (3)
将(3)代入(2)得
3x=2(1-3x)-5
3x=2-6x-5
9x=-3
x=-1/3
将x=-1/3代入(3)得
y=1-3(-1/3)
y=2
4x-5y=2 (2)
(1)*2-(2)得
5y=6y-2
y=2
将也代入(1)
2x=3*2
x=3
-6x+5y=3 (1)
3x=4y (2)
由(2)得
x=4/3y (3)
将(3)代入(1)得
-6*(4/3y)+5y=3
y=-1
将y=-1代入(3)得
x=4/3*(-1)
x=-4/3
2x+3y=5 (1)
3x=y-9 (2)
由(2)得
y=3x+9 (3)
将(3)代入(1)得
2x+3(3x+9)=5
11x=-22
x=-2
将x=-2代入(3)得
y=3*(-2)+9
y=3
3x=1-y (1)
3x=2y-5 (2)
由(1)得
y=1-3x (3)
将(3)代入(2)得
3x=2(1-3x)-5
3x=2-6x-5
9x=-3
x=-1/3
将x=-1/3代入(3)得
y=1-3(-1/3)
y=2
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