1.方程2x+y/2=5x+2y/4=1,求x+2y+1/2x—3y+7
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
不解方程2x+y=5;x-3y=1,求7y(x-3y)²-2(3y-x)³的值.
已知4x=9y求(1)x+y/y (2)y-x/2x
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y
化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
不解方程2x+y=6,x-3y=1,求7y(x-3y)^2-2(3y-x)^3 的值
圆x^2+y^2=1,求点[(x(x+y),y(x+y)]的轨迹方程
已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y
已知实数x,y满足方程x^2+y^2-4x-2y+1=0.求x^2+y^2+x+y的最大值和最小值.