x+2y=3 x+y+z=36 2x+y+z=15 2y=3z x-y=1 x+2y+z x-z=-1 2x+z-y=18 x+y_数学解答

x+2y=3 x+y+z=36 2x+y+z=15 2y=3z x-y=1 x+2y+z x-z=-1 2x+z-y=18 x+y+2z=17
x+2y=3 2y=3z x-y=-1
x+y+z=36 x-y=1 2x+z-y=18
2x+y+z=15 x+2y+z=16 x+y+2z=17

人气：229 ℃　时间：2020-02-05 13:08:13

解答

x+2y=3 2y=3z x-y=-1x+2y=3 ①2y=3z ②x-y=-1 ③①-③得 3y=4 ,得 y=4/3代入③,得 x=y-1=1/3代入②,得 z=2/3y=8/9x+y+z=36 x-y=1 2x+z-y=18 x+y+z=36 ①x-y=1 ②2x+z-y=18 ③①-②得 2y+z=35 ④2*①-③得 3y+z=54 ⑤...我修改完了，帮忙解一下第二个谢谢