{2x-3y=7 4x+9y=9答案
3x-4y+5=0,5x+2y=9(过程及答案)
9y=3x-(x-1),4(x+y)-(2x+4)=8y
3x+2=y 5X+4=Y 7X+6=Y 9X+8=y 11x=y要如何计算
3x+2=y 5x+4=y 7x+6=y 9x+8=y 11x=y
y-3x=2,y-5x=4,y-7x=6,y-9x=8,y-11x=0方程组,
3x+2=y 5x+4=y 7x+6=y 9x+8=y 11x=y 联立方程 有的话
化简求值:(7x-2y)(3x-2y-1)-(4x+3y)(9x+6y),其中x=2,y=-1
{4/(x+y)+6/(x-y)=3 {9/(x-y)-1/(x+y)=1
已知4x=9y求(1)x+y/y (2)y-x/2x
x+y=3 x+2y=9 3/x+1=y y-x=3 y=2x-3 y-3x=1 2(x+1)-y=6 7x-5y=-9
x-2y=9 x+y+z=7 2x-3y=12
已知x/y=3/2求代数式4x-9y/2x+3y