5x+10y=75 8x+6-5y=0 x=? y=?
已知x.x+y.y-6x-8y+25=0,求3x.x+5y的值
(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai
6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5
x+y=5; x^y+y^x=17
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
已知x*x+4x+y*y-2y+5=0,则x*x+y*y=?
y-3x=2,y-5x=4,y-7x=6,y-9x=8,y-11x=0方程组,
已知X,Y,满足(X+3Y)(X-3Y)=-10(Y^2-6/5)和2X(Y-1)+4(1/2X-1)=0
2X+Y+Z=10,X+2Y+Z=-6,X+Y+2Z=8 5X+4Y-3Y=13,2X-3Y+7Z=19,3X-Y=2X
若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y*
【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2=
已知x,y满足约束条件{2x+5y>=10,2x-3y>=-6,2x+y