-1 -2

1+x = 72x
1 2
1/1+1/x =1/72x
2 1 2 2
(72x /1)1/1+1/x =1/72x (72x/1)
2
72x +72x=1 got stuck here

I have no idea what this means.

Are you solving some equation?
What is the original equation?