若100^x=2,10^y=5

若7x+10y分之5x+y=1/2,则x/y= 若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y* 若【2x²-3y²-10y+5】²+根号x-2y,则x= y= (4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai 若3x-5y=0,则x+y/x=（）,x-y/y=（）,2x-3y/2x+3y=( ) 若x-y/x+y=5,求x-y/2x+2y+5x+5y/3x-3y的值 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 若4x-3y-6z=0,x+2y-7z=0,求代数式5x*5x+2y*2y-z*z/2x*2x-3y*3y-10z*10 若5x+3y=3x+4y=x+2y+6,则x+y=___ 已知x,y满足约束条件{2x+5y>=10,2x-3y>=-6,2x+y { x-y/7-x+y/10=1/2 {2(x-y)+5(x+y)=3 若x^2+y^2-8x-10y+41=0,求x/y+y/x的值