$\"\"$

\

The masses are $\"\"$ and $\"\"$ .

\

The coordinates points are $\"\"$ and $\"\"$ .

\

The moment of the $\"\"$ - axis is :

\

$\"\"$ .

\

$\"\"$

\

$\"\"$

\

The moment of the $\"\"$ - axis is:

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

The sum of the masses is:

\

$\"\"$

\

$\"\"$

\

$\"\"$ .

\

$\"\"$

\

Therefore center of the mass is:

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

The center of the mass of the given system of points is $\"\"$ .