已知实数x,y,z满足xy/x+y=2,xz/x+z=3,yz/y+z=4 求7x+5y-2z的值

已知实数x,y,z,满足那么x+y=6,z^2=xy-9,求(x+y)^z 已知实数x,y,z满足x=6-y,z^2=xy-9,求证：x=y 已知实数x .y.z.满足2^x=3^y=6^z 求证:xy+yz=xz 已知实数x,y,z满足x=6-y,z^2-4z+4=xy-9,求x,y,z的值 已知实数x,y,z满足x=6-y,z^2-4z+4=xy-9,求x,y,z的值. 已知实数x,y,z满足x+y=5,z^2=xy+y-9,那么x+2y+3z=?我很着急 已知实数x.y.z满足x+y=5及z的2次方=xy+y-9则x+2y+3z=? 已知实数x,y,z满足x+y=5,z^2=xy+y-9,那么x+2y+3z=? 已知实数x,y,z满足x-y=5,z^2=-xy-y-9,求x-2y+3z的值 已知实数x,y,z,满足x+y=5,z²=xy+y=9,求x+2y+3Z的值 已知实数x、y、z满足x＋y=5,z的平方=xy+y-9,那么x+2y+3z=( ) 已知实数x,y,z满足x=6-y,z²=xy-9,求证：x=y 已知实数x,y,z满足x+y=6,z的平方=xy-9,求证x=y 已知实数xy满足x+2y 已知实数xy满足 x+y-2 已知实数x,y,z,满足x+y=4及xy=z^2+4,求x+2y+3z的值求教啊 已知实数x,y,z满足x+3y=6,2xy-z^2=6,求x、y、z的值 已知实数x,y,z满足x+y=4及xy=z²+4,求x+2y+3z的值