Let the three straight lines be given by

a_{1}x + b_{1}y + c_{1} = 0

a_{2}x + b_{2}y + c_{2} = 0

a_{3}x + b_{3}y + c_{3} = 0

If the three straight lines are concurrent, then the point of intersection of any two straight lines lies on the third straight line.

The condition for the three straight lines to be concurrent is