$\"\"$ \ \

The points on the line equations are $\"\"$ and $\"\"$ .

From problem (39):

The parametric equations for line equation are $\"\"$ and $\"\"$ .

Substitute $\"\"$ and $\"\"$ in $\"\"$ .

$\"\"$

Substitute $\"\"$ and $\"\"$ in $\"\"$ .

$\"\"$

The parametric equations for line equation are $\"\"$ and $\"\"$ .

$\"\"$ \ \

The parametric equations for line equation are $\"\"$ and $\"\"$ .