x+y=15 2x+2*6+4*4+(y-10)*8=44怎么解?

{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 2（x+y)-3(x-y)=3 ,4(x+y)+3(x-y)=15 （x+y）/2- x-y/2=6 3(x+y)=4(x-y) x+y/3+x-y/2=6 4(x+y)-2(x-y)=40 x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20 {(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20 4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6 解方程组 10（x-y)=3(x+y)+15 6(x+y)=4(2x-y)+1610（x-y)=3(x+y)+156(x+y)=4(2x-y)+16 解方程组 10（x-y)=3(x+y)+15 6(x+y)=4(2x-y)+1610（x-y)=3(x+y)+156(x+y)=4(2x-y)+16分开的。 (x-y) (x-2y)+(x+2y) (x-3y)-2(x-3y) (x-4y)= (x-4y)(2x+y)= 已知x^2+y^2+13-4x+6y=0,求(2x-y)^2-2(2x-y)(x+2y)+(x+2y)^2 解二元一次方程组：3(x+y)-4(x-y)=4,x+y/2+x-y/6+1x+y/2+x-y/6+1=1 4x方y/(x-2y)(x+2y)怎么算[x方/x-2y]-4x方y/(x-2y)(x+2y)=? 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 已知x.x+y.y+8x+6y+25=0,求代数式(x.x-4y.y)/(x.x+4xy+4y.y)-x/(x+2y)的值 例X=1 y=21.X+Y=5 X-Y=15 2.2X+3Y=4 5X+6Y=7 3.X+3Y=5 3X+Y=-1 4.2X+Y=3 3X+5Y=11 5.4X+3Y=6 2X+Y=4 6.X+Y=180 X=3Y-10 7.3X-2Y=3 2X-Y=7 8.5X+3Y=7Y X+Y=45 9.3X+4Y=126X+8Y=24 X:6Y=1:4 10.X+Y=138 X-45=Y+53 11.X+Y=60 14Y=20X 12.2X+3Y=15.5 5X+6Y=35 13.X+Y=170 3 [(x+y)(x-y)-(x-y)²+2y(x-y)]÷4y