解方程组：1.{x+y=4①,2x-y=5 ② 2.{2x+3y=4①,5x+6y=7②3.{3分之x+y+2分之x-y=6 ,3（x+y)-2（x-y)=284.{5分之x=2分之y ,3x-2y=225.{2x-3y/4+2（x+2y）=1,3（2x-3y)/4-x+2y/5+4=0

3(x+y)—4(x-y)=4,(x+y/2)+(x-y/6)=1.解方程组 解方程组,x+y/2=3x-2y=10+6x+y/4, 解方程组3x+5(x+y)=2 3y-2(x+y)=4 解方程组｛ 3x-4y(x-y)=3 { 2x-3y=1 解方程组x+y/3=x-y/4 2x+3y=11 解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7 解方程组 y=2x x+y=3 解方程组x^2-y^2=x+y 4x^2-y^2+2x-y=0过程 解方程组2(x-y)/3-x+y/4=-1 6(x-y)-4(2x-y)=16 解方程组：2(x-y)/3-x+y/4=-1 ,6(x+y)-4(2x-y)=16 解方程组;x+y/2=x-y/3=6 4(x+y)-3(x-y)=-20 解方程组 4(x+y)-(2x-y)=14 ,3(x+y)-2(2x-y)=8 解二元一次方程组3(x+y)-4(x-y)=4 x+y/2+x-y/6=1 解方程组3(x+y)-4(x-y)=4和(x+y)/2+(x-y)/6=1kkkkkkkk 解方程组3(x+y)-4(x-y)=4,x+y除以2+x-y除以6=1 解方程组 X+Y/2+X-Y/3=6 4[X+Y]-5[X-Y]=2 解二元一次方程组{x+y/2+x-y/3=6,4(x+y)-2=5(x-y) 解方程组2分之x+y+3分之x-y=6 4(x+y)-5(x-y)=2