求2x+4y=1,2x-3y=6

已知：2x+y=6,x-3y=1 求7y(x-3y)(x-3y)-2(3y-x)(3y-x) 已知x-y=1,求[(x+2y)^2+(2x+y)(x-4y)-3(x+y)(x-y)]除以y的值大神们帮帮忙 已知x-y=1,求[(x+2y)²+(2x+y)(x-4y)-3(x+y)(x-y)]÷y的值 {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 求值域 1,y=(x+2)/(x*x+3x+6) 2,y=3x/(x*x+4) (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 x*y=6x-y=1求X Y是多少?X=3 Y=2 求公式! x+y/2+ x-y/2=6 2(x+y)-3x+3y=24 求X Y 已知2y-x=-3,求[4y(2x-y)-2x(2x-y)]/(2x-y {(x+y)/2+(x-y)/3=1,(x+y)-5(x-y)=2.求x=?,y=? 2x+4y=3 -3x-2y=1 ..求x和y 1.(x-2y)(x+2y)-(x平方+y)(x平方-y) 2.(2x-y)(y+2x)-(2y+x)(2y-x)3.已知：x+y=6,x平方-y平方=48,求x,y的值4.x平方-2x分之x+2 -- x平方-4x+4分之x-1 4x-3y=5 x^2+y^2=1 求x,y 3x+4y-5=0 x^2+y^2=1求x.y 已知x-2y=2,求4x-y-8分之3x+y-6 2^x=4^(y-1) 27^y=3^(x+1)求x-y 已知3x-4y/2x+y=1/2 求x/y的值