1. Draw a straight line with a ruler, and take two points A and B on the straight line (A and B are not coincident).

2. Make two equal circles with two points A and B as the center and half the length of AB as the radius, and get two intersection points C and D, and the distances from the two intersection points C and D to A and B are equal (both radii are equal).

3. The connecting line CD connecting the two intersection points C and D is the vertical line (the point with the same distance to both ends of the line segment is on the middle vertical line of this line segment, and the connecting line of these two points is the middle vertical line of this line segment, that is, vertical).

Extended data:

The basic method of ruler drawing, the following are the basic methods available in ruler drawing, also known as drawing public law. Any step of ruler drawing can be decomposed into the following five methods:

1, you can make a straight line through two known points.

2, known center and radius can be made into a circle.

3. If two known straight lines intersect, you can find the intersection point.

If a known straight line intersects a known circle, the intersection point can be found.

5. If two known circles intersect, the intersection point can be found.

References:

Baidu Encyclopedia-Ruler Drawing