Draw any line segment . Take any point not on it. Through , draw a perpendicular to (use ruler and set-square).
Step 1. Draw a given line segment and then place a point outside the line segment as follow:
Step 2. Next, arrange a set square on so that one of its right angles arms are aligned with as follows:
Step 3. Now, align the ruler with the edge of the established square that is opposite the right angle as follows:
Step 4. Hold the ruler in place and slide the set square along the ruler until the point reaches the other arm of the set square as follows:
Step 5. Finally, draw a line along the established square's boundary that passes through point . We now have the necessary line perpendicular to as follow:
Hence, the diagram is shown below: