变式:已知x,y满足4x+7y=222,5x+6y=217,则x-y=?
变式:已知x,y满足4x+7y=222,5x+6y=217,则x-y=?
已知x,y满足x²+y²-4x+6y+13=0则(3x+y)²-(3x+y)(3x-y)的
已知实数x,y满足|x|+x+y=10、x+|y|-y=12,则x+y的值?
已知实数x.y满足根号(x+y-8)+根号(8-x-y)=根号(3x-y-4)+根号(x-2y+7),求x,y
已知X和Y满足3X+4Y=2,X-Y-1/7
已知正实数x,y满足x+2y=4,则1x+1y
已知实数x、y满足x²+y²+4x-6y+13=0
已知X,Y,满足(X+3Y)(X-3Y)=-10(Y^2-6/5)和2X(Y-1)+4(1/2X-1)=0
已知x,y满足约束条件{2x+5y>=10,2x-3y>=-6,2x+y
已知x,y满足约束条件x-y+5>=0 x+y>=0 X
已知x*x+4x+y*y-2y+5=0,则x*x+y*y=?
已知实数x,y满足5x²+2y²+1=6xy+4x-2y,则x²-xy+2000y