求 1/2x-4y=30,y-2x=15 2元1次组解
已知4x=9y求(1)x+y/y (2)y-x/2x
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x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
已知x²+y²+5=2x+4y,求代数式(2x²-(x+y)(x-y))x((x+y-1)
x+y=1,xy=-1/2,求x(x+y)(x-y)-x(x+y)2
2^x=4^(y-1) 27^y=3^(x+1)求x-y
已知3x-4y/2x+y=1/2 求x/y的值
已知方程组4x+2y=1,20x+8y,求x,y
4/X+1/Y=2,XY=-1,求代数式4Y-X/X-2Y/(x+2y-12Y²/x-2y)的值
已知x,y满足y^4+2x^4+1=4x^2y,求x,y的值
已知X:Y=1:3,Y:Z=5:4 (1)求X:Y:Z (2)如果X+Y+Z=96,求X,Y,Z的值 3元1次方程