已知16x^2=9,y^3=8,求x+y的值

已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(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|=2,|y|=3,|x+y|=-(x+y)求x-y 已知16x^2=9,y^3=8,求x+y的值 23.已知(x+y)3次+8*x的平方*y-16x*y的平方=18,x+2y=3,求x,y的值 已知:3x-5y=0,求x/y,x-y/y,x-y/x 已知,X:Y=3:2,求代数式4X-9Y:2X+3Y 已知x/y=3/2求代数式4x-9y/2x+3y 已知x-2y=2,求4x-y-8分之3x+y-6 已知2x-y/x+2y=3,求2(2x-y)/x+2y-9(x+2y)/2x-y+3的值. 已知实数x.y满足根号(x+y-8)+根号(8-x-y)=根号(3x-y-4)+根号(x-2y+7),求x,y 已知x^2+y^2-16x-8y+25=0,求y/x-x/y的值 已知2x+2y=-8,4x+y=15求（x-y)^-(3x+2y)^ 已知：x+9y=y-3x,求(x^2-y^2)/(x^2+y^2)的值RT 已知X*X+Y*Y+6X-8Y+25=0 求（Y/X)+(X/Y)-2=? 已知2y-x=-3,求[4y(2x-y)-2x(2x-y)]/(2x-y 已知x^2-8x+y^2-y+16又1/4=0,求[(x+y)(x-y)-(x+y)^2-2y(x-3y)]÷4y的值