5x-y=110 (1) 9y-x=110 (2)用代入法解方程组

4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 ｛x-y=4 ｛5x-y=110 4x-y=－1 9y-x=110 x+(9-8-y)=10 y+y-(9-8-y)=2 x-y=xx-9.9x xy=11y-1 y=? x=? x+y-xy=?x+(9-8-y)=10y+y-(9-8-y)=2x-y=xx-9.9xxy=11y-1 y=?x=?x+y-xy=? 5x-y=110 9y-x=110 [(y*y*y-y)/(xy+1)*(xy+1)-(x+y)*(x+y)]/[(x+y)*y/(x+1)]其中x=-11,y=1/12,化简再求值. 3(x+y)-2(x-y)=11 4(x+y)+3(x-y)=9 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 x=5,y=110{x=y/x; y=y-x;}while(y>=1); 求x y {6(x-y)-7(x+y)=21 {2(x-y)-5(x+y)=-1 (x+y)/6+(x-y)/10=1,(x+y)/6-(x-y)/10=5 (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) (x-y)/4+(x+y)/5=1/4 (x+y)/9-(x-y)/3=//2(x-y)/4+(x+y)/5=1/4(x+y)/9-(x-y)/3=//2 x+y=5① x=3y+2① 9x-5y=1① 3x-2y=11① x-2y=y+1① 2x-y=7② x+3y=8② 6x-7y=2② 2x+3y=16② 2x-3y=10②3x+2y=y+1①2x-3y=10②D 很多很多数学题都是求x,y的1.2x-y=5 3x+4y=22.5x-y=110 9y-x=1103.8x+3y=7 5x-3y=6 4x+3y=6x-y=-25.4x-5y=1 2x-y=56.4x+3y=6 5x+6y=3 接二元一次4(x+y)-3(x-y)=9;5(x-y)+2(x+y)=11 解方程组 3(x+y)-2(x-y)=9,5(x+y)+2(x-y)=-1 解方程组:{3(x+y)-2(x-y)=9,5(x+y)+2(x-y)=-1} {x+y-z=11 y+z-x=5 z+x-y=1