Parallel straight lines are studied at geometry lessons at school. But the concept about them and skill of their construction is useful in everyday life and professional activity far behind a threshold of school.
It is required to you
- Paper, pencil, ruler, compasses.
Instruction
1. To construct parallel straight lines, we use following characteristics: 1) Straight lines either are crossed, or not crossed. The straight lines which never are crossed are called parallel. 2) The distance on a perpendicular between straight lines in all points has to be identical. 3) Through the point which is not lying on this straight line it is possible to construct only one parallel to it direct.4) If two straight lines in the plane are perpendicular to the third straight line, then they are parallel.
2. The first you sposobnachertit a straight line. Note on it several points. The more points, the error is less. By means of a ruler set a certain distance on compasses. It will be radius. From everyone to the point noted by you on a straight line carry out a circle. Now carry out a tangent to these circles. Received the straight line parallel initial, it approaches under the characteristics stated above.
3. For check lower from points of contact of the constructed straight lines and a circle a perpendicular on the first straight line. The received perpendiculars have to be equal.
4. To the second sposobtakzha draw a straight line and note on it several points. Restore perpendiculars to a straight line from noted points. On the received perpendiculars postpone identical pieces and designate the received points. Through the received points draw a straight line. It will be parallel to an initial straight line.