解方程组:2(x-y)/3-x+y/4=-1 ,6(x+y)-4(2x-y)=16

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解方程组:2(x-y)/3-x+y/4=-1 ,6(x+y)-4(2x-y)=16

解方程组:2(x-y)/3-x+y/4=-1 ,6(x+y)-4(2x-y)=16
解方程组:2(x-y)/3-x+y/4=-1 ,6(x+y)-4(2x-y)=16

解方程组:2(x-y)/3-x+y/4=-1 ,6(x+y)-4(2x-y)=16
2(x-y)/3 - x+y/4=-1 (1)
6(x+y)-4(2x-y)=16 (2)
(1)方程两边同乘以12得
8(x-y)-3(x+y)=-12
合并同类项得
5x-11y+12=0 (3)
(2)合并同类项得
10y-2x-16=0 (4)
(3)*2+(4)*5得
28y-56=0
所以 y=2
把y=2代入(1)得
x=2

x=4/5, y=44/25
https://www.wolframalpha.com/input/?i=2%28x-y%29%2F3-x%2By%2F4%3D-1+%EF%BC%8C6%28x%2By%29-4%282x-y%29%3D16