{x+y=500000 5%x+7.5%y=3000 解这个二元一次方程

（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=40,(X*Y)/(X+Y)=7.5 y-x=x-5 x+y=5; x^y+y^x=17 y=|-x.x+4x+5| 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＝ (X-Y)(X+Y)=5 能解么 5x-4y(y-x)=? (9X+5Y)/(X+Y)=7.5,求X/Y=? 用递归法求y=x-(x*x*x/3!)+(x*x*x*x*x/5!)-(x*x*x*x*x*x*x/7!)+. {x+y=500000 5%x+7.5%y=3000 解这个二元一次方程 x-y+5x-4x= ?x-y+5x-4x= ? x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 Y={X (-5 Y={X (-5 x*x+2x+y*y-4y+5=0 x= y=