In geometry often it is necessary to build perpendiculars. A problem of creation of a perpendicular by means of compasses and a ruler - one of basic in geometry. In particular, on creation of a middle perpendicular.
It is required to you
- Compasses, ruler, pencil
Instruction
1. Let us have a piece. Let's consider how to construct a middle perpendicular to this piece.
2. Through the ends of a piece carry out two circles with identical radiuses. It is not obligatory to build all circle, enough to receive only of a point of intersection.
3. Through points of intersection of circles draw a straight line. You received a middle perpendicular to the set piece.
4. Let now to us the point and a straight line be set. It is necessary to carry out a perpendicular from this point to a straight line. Put a compasses needle in a point. Carry out a circle of any radius (radius has to be more than a distance from a point to a straight line that the circle could cross a straight line in two points). Now you have two points on a straight line. These points create a piece. Construct a middle perpendicular to a piece which ends are the received points, on the algorithm considered above. The perpendicular has to pass through the initial point.