1/5x+1/3y=2/5等价于3x+5y=6 ⑴0.5x-0.3y=0.2等价于5x-3y=2 ⑵⑴*3+⑵*5:34x=28 x=14/17⑴*5-⑵*3:34y=24y=12/17
1/5x+1/3y=2/5~1/10x+1/6y=1/50.5x-0.3y=0.2~0.1x-0.06y=0.04y=3/2x=-1/2
