\"\"

\

The weights balanced opposite ends of the beam are \"\" and \"\".

\

The length of the beam is \"\",

\

The system is in equilibrium \"\".

\

Substitute \"\", \"\" and \"\".

\

\"\"

\

\"\"

\

\"\"

\

\"\"

\

\"\"

\

\"\".

\

\"\"

\

\"\".