Draw any line segment . Mark any point on it . Through , draw perpendicular to (use ruler and compasses).
Steps of construction;
Step-1 Draw a given line segment and mark any point on it.
Step-2 With as a centre and convenient radius, construct an arc intersecting the line segment at two points and respectively.
Step-3 Now, with and as centres and radius greater than , construct arcs on other side. Let these arcs intersect each other at .
Step-4 Join .
Thus, is the required perpendicular to .