2x-6y=10、6x+2y=90
【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2=
6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5
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
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于
已知x,y满足约束条件{2x+5y>=10,2x-3y>=-6,2x+y
已知x^2+y^2--6x--2y+10=0,求x+y/x--y
已知x^2-2x+y^2+6y+10=0,求分式x-y/x+y的值
解方程组 10(x-y)=3(x+y)+15 6(x+y)=4(2x-y)+16
已知:4x^2+y^2-4x-6y+10=0,求y/x-x/y的值