$\"\"$

The endpoints are $\"\"$ and $\"\"$ .

The midpoint of a segment with endpoints $\"\"$ is $\"\"$

$\"\"$ (Substitute: $\"\"$ )

$\"\"$ (Add: $\"\"$ )

$\"\"$ (Divide: $\"\"$ )

The midpoint is $\"\"$ . $\"\"$

The midpoint of the segment with endpoints $\"\"$ and $\"\"$ is $\"\"$ .