5x-7y-5=0 3x-2y=-8要过程

（x+y-5)*（x+y-5)+（x-y+3)=0 x*x-y*y 已知:3x-5y=0,求x/y,x-y/y,x-y/x x+y=1 5x-2y=8 3x-y=7 2x-y=3x表示y和用y表示x 已知(3x+1)(3x-3)-3x+2)^2=-7,(y+7)(y-7)-y(y-7)=0,求8y^2-5y(-y+3x)+4y(-4y-5/2x)的值 y-3x=2,y-5x=4,y-7x=6,y-9x=8,y-11x=0方程组,无 3x+2=y 5X+4=Y 7X+6=Y 9X+8=y 11x=y要如何计算 {x+y=1 ,xy=-6{x(2x-3)=0,y=x²-1{(3x+4y-3)(3x+4y+3)=0,3x+2y=5{(x-y+2)(x+y)=0,x²+y²=8{(x+y)((x+y-1)=0,(x-y)(x-y-1)=0 求过两圆x²+y²+2x-3y-9=0和x²+y²-2x+5y=0的交点 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) {2x+y/3-2y=0 2(2x+y)-5=7y x+y=5,2x+y=8,x-2y=0,3x+2y=8 已知|5x-y-8|+(7y-x+2)=0则4x+6y 怎么解下列方程组?(1).X=Y+1 Y+X=5 (2)2X-3Y=4 1/2Y-X=1 (3)X+2=3Y 2X=3Y (4)3X+7=7 5X-2Y=8(5)2X+3Y=5 4X-Y=3 (6)3X-2Y=4 5X+3Y-13=0 (7)X+5Y=12 2X-5Y=-6 (8)X-3Y=-3 3X+Y=11 (要写过程) 解下列方程组：{x(2x-3)=0,y=x²-1{(3x+4y-3)(3x+4y+3)=0,3x+2y=5{(x-y+2)(x+y)=0,x²+y²=8{(x+y)((x+y-1)=0,(x-y)(x-y-1)=0 (4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuaihuajian 先化简,再求值 [2/3x - 2/x+y（x+y/3x -x-y）]*x/x-y,其中5x+3y=0 先化简,再求值:[3x-2/x+y(x+y/3x-x-y)]/(x-y/x),其中5x+3y=0 已知7x+5y/2y-x=3/2,且x≠0,求X/x-4y