3x+1=4y-x=y+2 4x+5y=2710x+3y=20
3个回答
y+2=4y-x得x=3y-2
3x+1=4y-x有4x=4y-1
联解得x=5/8,y=7/8
(1)式*3-(2)式*5得
38x=19 x=0.5 y=5
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