1/2x-y=1/3z ①
x-y-1=z ②
4x-5y+3z=5 ③
整理①、②得
3x-6y-2z=0 ④
x-y-z=1 ⑤
④-⑤*2得 x-4y=-2 ⑥
③+⑤*3得 7x-8y=8 ⑦
⑦-⑥*7得20y=22
解得y=11/10
代入⑥得x=12/5
代入②得z=3/10