解复杂的二元一次方程2(x-y) x+y--------- - ------- =-13 46(x+y)-4(2x-y)=16无过程不接受
2019-04-13
解复杂的二元一次方程
2(x-y) x+y
--------- - ------- =-1
3 4
6(x+y)-4(2x-y)=16
无过程不接受
优质解答
2(x-y) x+y
--------- - ------- =-1
3 4
化简得:8(x-y)-3(x+y)=-12
8x-8y-3x-3y=-12
5x-11y=-12 ①
6(x+y)-4(2x-y)=16
6x+6y-8x+4y=16
-2x+10y=16
x-5y=-8
x=5y-8 ②
②代入①得:5(5y-8)-11y=-12
25y-40-11y=-12
14y=28
y=2
x=5y-8=5x2-8=2
所以x=2,y=2
2(x-y) x+y
--------- - ------- =-1
3 4
化简得:8(x-y)-3(x+y)=-12
8x-8y-3x-3y=-12
5x-11y=-12 ①
6(x+y)-4(2x-y)=16
6x+6y-8x+4y=16
-2x+10y=16
x-5y=-8
x=5y-8 ②
②代入①得:5(5y-8)-11y=-12
25y-40-11y=-12
14y=28
y=2
x=5y-8=5x2-8=2
所以x=2,y=2