3x-5y+2=0 9x+6y-8=0
y-3x=2,y-5x=4,y-7x=6,y-9x=8,y-11x=0方程组,
已知x.x+y.y-6x-8y+25=0,求3x.x+5y的值
求解 3x=6y-2 3x-4y=2 6x-3y=-5 4x-9y+1=0 4(2x+y)-5(2x-y)=3 2(2x
【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2=
微分方程(1)(y'')^2+5y'-y+x=0;(2)y''+5y'+4y^2-8x=0;(3)(3x+2y)dx+(
若2x-3y+4=0则x(x*x-1)+x(5-x*x)-6y+7
3x-2y=9 x-3y=2 x+y=5 x+2y=3 y=x 2x+y=8
已知4x^2+y^2-4x-6y+10=0,求(2\3x根号9x+y^2根号x/y^3)-(x^2-5x根号y\x) 拜
x^2+y^2-4x-6y+13=0,求(2/3根号9x+y^2根号x/y^3)-x^2根号1/x-5x根号y/x)的值
若3x-5y=0,则x+y/x=(),x-y/y=(),2x-3y/2x+3y=( )
已知X.x+y.y-4x+2y+5=0,求4X.X-12X Y+9Y.y的值
3x+2=y 5X+4=Y 7X+6=Y 9X+8=y 11x=y要如何计算