{6x+y=25 9x-3y=6 {6x-7y=19 3x+4y=2

【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2= 已知x.x+y.y-6x-8y+25=0,求3x.x+5y的值 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 2(x+y)-3(x-y)=1 6(x+y)+(x-y)=51 {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 x+y/2+x-y/6=5 2(x+y)-3(x-y)=-2 6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5 （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 若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于 6(x+y)的平方-11(x+y)(x-y)+3(x-y)的平方=? 已知X*X+Y*Y+6X-8Y+25=0 求（Y/X)+(X/Y)-2=? x+y/2+ x-y/2=6 2(x+y)-3x+3y=24 求X Y y=-6/x (x 已知6x+2y/9x-3y=6,那么(3x+y)平方/x平方-y平方 解二元一次方程 {3(x+y)-4(x-y)=-9 x+y/2+x-y/6=1