若3^x=4,3^y=6,求9的2x-y+27的x-y的值

若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 若3^x=4,3^y=6,求9^2x-y+27^x-y的值. 若／X+Y-9／+（2X-Y+3)=0求X与Y的值 若x*x-4y*y=-15,x+2y=3,求x和y的值 若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值 已知x-y=1,求[(x+2y)^2+(2x+y)(x-4y)-3(x+y)(x-y)]除以y的值大神们帮帮忙 已知x-y=1,求[(x+2y)²+(2x+y)(x-4y)-3(x+y)(x-y)]÷y的值 x^2+4y^2-6x+4y+10=0,求x^4-y^4/(x+2y)(x-2y)*x+2y/xy^2+y^3除以（x^2+y^2/y)^2的值 已知x²+y²+6x-2y+10=0,求8y分之9x²-y² + 4分之y-3x的值 化简求值：已知x、y满足：x^2+y^2-4x+6y+13=0 求代数式 的值.(3x+y)^2-3(3x-y)(x+y)-(x-3y)(x+3y)急用！ 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 (-x+6):(x-y);(4x+y)=3;14:1,求x+y的值. 已知(x+2y)(2x-3y)=y(y-4x),试求x/y的值 已知x,y满足{3x-y=9 {x-3y=0 求x+2y+ 4y的平方/x-2y -4x的平方y/x的平方-4y的平方 若(-x+6):(x-y):(4x+y)=3:14:1,求x+y 若(-x+6):(x-y):(4x+y)=3:14:1,求x+y y=3(x-y),x=2(x-y)求x,y的值 若x+y^2-8y-6y+25=0,试求3x+4y的值xiexie!