2x+3y=19.5 5x+6y=45求x=多少 y=多少

已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 2x+3y=19.5 5x+6y=45求x=多少 y=多少 6x+5Y=31 2X+3Y=17求X求 Y (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) 已知:3x-5y=0,求x/y,x-y/y,x-y/x x+y/2+ x-y/2=6 2(x+y)-3x+3y=24 求X Y {(x+y)/2+(x-y)/3=1,(x+y)-5(x-y)=2.求x=?,y=? 6x-2y=5 8x-3y=-5 求x,y 已知：2x+y=6,x-3y=1 求7y(x-3y)(x-3y)-2(3y-x)(3y-x) 5X+Y=3 X+5Y=2 求x和y.5X+Y=3X+5Y=2求x和y. 1、(-y^3)^5/y^3/ y^2+2(-y)^102、(x-y)^7/(y-x)^6+(x+y)^3/(x+y)^23、已知X^a=5,x^b=3,求X^(3a-2b)的值 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 3x+5y=45 求x.y 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 已知3x =2y 求x/x+y+y/x-y-y²/x²-y² 已知x^3+xy^2+x+x^2y+y^3+y=0,求5x-6y/3x+4y的值. √x(√x+2√y)=√y(6√x+5√y,求x-3√xy+2y/x+√xy-6y