已知：xy/x+y=12,xz/x+z=15,yz/y+z=20.求x,y,z的值.应该是xy/(x+y)=12,xz/(x+z)=15,yz/(y+z)=20

Question

已知：xy/x+y=12,xz/x+z=15,yz/y+z=20.求 x ,y ,z的值.
应该是 xy/(x+y)=12,xz/(x+z)=15,
yz/(y+z)=20

Answer 1

xy/(x+y)=12,xz/(x+z)=15, yz/(y+z)=20
(x+y)/xy=1/12,(x+z)/xz=1/15,(y+z)/yz=1/20
1/y+1/x=1/12,1/z+1/x=1/15,1/z+1/y=1/20
1/x=3/20,1/y=2/15,1/z=7/60
x=20/3,y=15/2,z=60/7