3(x+y)-4(x-y)=4 x+2y+3z=5x+y/2+x-y/6=1 2x+3y+6z=95x+3y+9z=15 3(x+y)-4(x-y)=4 x+2y+3z=5 两式一道!(二元一次方程组)x+y/2+x-y/6=1 2x+3y+6z=9 5x+3y+9z=15 (三元一次方程组)
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![3(x+y)-4(x-y)=4 x+2y+3z=5x+y/2+x-y/6=1 2x+3y+6z=95x+3y+9z=15 3(x+y)-4(x-y)=4 x+2y+3z=5 两式一道!(二元一次方程组)x+y/2+x-y/6=1 2x+3y+6z=9 5x+3y+9z=15 (三元一次方程组)](/uploads/image/z/11459145-57-5.jpg?t=3%28x%2By%29-4%28x-y%EF%BC%89%3D4+x%2B2y%2B3z%3D5x%2By%2F2%2Bx-y%2F6%3D1+2x%2B3y%2B6z%3D95x%2B3y%2B9z%3D15+3%28x%2By%29-4%28x-y%EF%BC%89%3D4+x%2B2y%2B3z%3D5+%E4%B8%A4%E5%BC%8F%E4%B8%80%E9%81%93%EF%BC%81%EF%BC%88%E4%BA%8C%E5%85%83%E4%B8%80%E6%AC%A1%E6%96%B9%E7%A8%8B%E7%BB%84%EF%BC%89x%2By%2F2%2Bx-y%2F6%3D1+2x%2B3y%2B6z%3D9+5x%2B3y%2B9z%3D15+%EF%BC%88%E4%B8%89%E5%85%83%E4%B8%80%E6%AC%A1%E6%96%B9%E7%A8%8B%E7%BB%84%EF%BC%89)
3(x+y)-4(x-y)=4 x+2y+3z=5x+y/2+x-y/6=1 2x+3y+6z=95x+3y+9z=15 3(x+y)-4(x-y)=4 x+2y+3z=5 两式一道!(二元一次方程组)x+y/2+x-y/6=1 2x+3y+6z=9 5x+3y+9z=15 (三元一次方程组)
3(x+y)-4(x-y)=4 x+2y+3z=5
x+y/2+x-y/6=1 2x+3y+6z=9
5x+3y+9z=15
3(x+y)-4(x-y)=4 x+2y+3z=5 两式一道!(二元一次方程组)
x+y/2+x-y/6=1 2x+3y+6z=9 5x+3y+9z=15 (三元一次方程组)
3(x+y)-4(x-y)=4 x+2y+3z=5x+y/2+x-y/6=1 2x+3y+6z=95x+3y+9z=15 3(x+y)-4(x-y)=4 x+2y+3z=5 两式一道!(二元一次方程组)x+y/2+x-y/6=1 2x+3y+6z=9 5x+3y+9z=15 (三元一次方程组)
3(x+y)-4(x-y)=4x+2y+3z=5 .1
x+y/2+x-y/6=1 2x+3y+6z=9 .2
5x+3y+9z=15 .3
1式*2-2式得:6X+Y=1
1式+2式-3式得:X+2Y=-1
3式-2式得:X+Z=2
6X+Y=1
X+2Y=-1
X+Z=2
X=3/11.
Y=-7/11
Z=19/11
∵3(x+y)-4(x-y)=4即:3x+3y-4x+4y=7y-x=4⑴
x+2y+3z=5⑵
x+y/2+x-y/6=1即:3(x+y)+x-y=6=4x+2y=6⑶
2x+3y+6z=9 ⑷
5x+3y+9z=15 ⑸
∴由⑴乘以4加⑶得
28y-4x+4x+2y=16+6=2...
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∵3(x+y)-4(x-y)=4即:3x+3y-4x+4y=7y-x=4⑴
x+2y+3z=5⑵
x+y/2+x-y/6=1即:3(x+y)+x-y=6=4x+2y=6⑶
2x+3y+6z=9 ⑷
5x+3y+9z=15 ⑸
∴由⑴乘以4加⑶得
28y-4x+4x+2y=16+6=22
∴y=11/15 x=17/15
把y=11/15 x=17/15代入⑷得:
在=68/15
什么题啊?已知给得太多了
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