1.4Y=X 5X+6Y=39

1.4Y=X 5X+6Y=39 (x+y)/6+(x-y)/10=1,(x+y)/6-(x-y)/10=5 {6(x-y)-7(x+y)=21 {2(x-y)-5(x+y)=-1 x+y/2+x-y/6=5 2(x+y)-3(x-y)=-2 6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5 （5x-6y)(x+y)=0(x不等于y),则y/x= 数学一元二次方程组1.4/x+y+6/x-y=39/x-y-1/x+y=1用换元法求 （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/x-x+y/y-(x+y)(x-y)/y² y/x=2 1:4(x-100)+3y=5 2:6(x-y)-2(x+y )=14 x-100=-y 3(x-y)+(x+y)=5 先无视上面的1.4(x-100)+3y=5x-100=-y2.6(x-y)-2(x+y )=143(x-y)+(x+y)=5 x+y=5; x^y+y^x=17 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 若(X×X+Y×Y)(X×X+Y×Y-5)=36,则X×X+Y×Y＝ 化简 x / y(x+y) - y / x(x+y) = (X-Y)(X+Y)=5 能解么 5x-4y(y-x)=? 3x+5y-(x+y)=6 2(x+y)-3x=-7