x/y=7/5,求3x+y/X-y的值

3(x-5)-8y=-x-(-0.5y)=7,求x,y的值 x/y=7/5,求3x+y/X-y的值 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 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 y=3(x-y),x=2(x-y)求x,y的值 已知|3x-y|+|x+y|=0,求x-y除以x*y的值. 已知:3x-5y=0,求x/y,x-y/y,x-y/x 已知x.x+y.y-6x-8y+25=0,求3x.x+5y的值 x-y=3 7-x+y-y平方+X平方已知x-y=3 求代数式7-X+y-(y-x)²的值 已知（x+y）2 =2,(x-y)3 =3,求(x+y)7(x-y)2(x+y)3(y-x)4 的值 若x-y/x+y=5,求x-y/2x+2y+5x+5y/3x-3y的值 若x+y分之x-y=3,求式子x+y分之5(x-y)—2(x-y)分之x+y的值 若x-y分之x+y=3,求式子x+y分之5(x-y)—2（x-y）分之x+y的值 已知2x-y/7x+5y=2/3且y≠0,求x/y的值 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 已知x+y=6,xy=7,试求x*x+y*y,x*x-y*y的值 x/3=y/4,求(x*x-xy)/(x*x+y*y)的值