x/4+y/3=1 x-2y=2x=2+2y 代入(2+2y/)4+y/3=13(2+2y)+4y=126+10y=12y=3/5 x=16/55x+2y=10 (8x+3y)(10x+4y-10)=16010x+4y-10=2(5x+2y)-10 代入8x+3y=16 联立5x+2y=10x=2 y=0y+x+3=3x+2y=4x+y=13x+2y=4联立x=2 y=-1...