The octagon is, in essence, two squares, displaced relatively each other on 45 ° and connected at tops by the uniform line. And therefore, in order that it is correct to represent such geometrical figure, it is necessary a firm pencil very accurately, by rules to draw a square or a circle with which and to carry out further actions. The description is focused on length of the party equal of 20 cm. So, at arrangement of the drawing consider that vertical and horizontal lines 20 cm long found room on the sheet of paper.
It is required to you
- Ruler, rectangular triangle, protractor, pencil, compasses, sheet of paper
Instruction
1. Way 1. Draw below a horizontal line 20 cm long. Then on the one hand note a protractor a right angle which makes 90 °. The same can be made by means of a direct triangle. Draw a vertical line and note 20 cm. Do the same manipulations on the other hand. Connect two received points a horizontal line. As a result the geometrical figure – a square turned out.
2. To construct the second (displaced) square, the center of a figure is required. For this purpose divide each party of a square into 2 parts. Connect at first 2 points of the parallel top and lower parties, and then points of sides. Draw through the center of a square 2 straight lines perpendicular relatively each other. Beginning from the center, measure on new straight lines length on 10 cm that as a result will give 4 straight lines. Connect 4 received external points among themselves therefore the second square will turn out. Now connect each point from 8 received corners among themselves. Thus, will be nacherchen an octagon.
3. Way 2. For this purpose compasses, a ruler and a protractor are required. From the center of the sheet by means of compasses draw a circle with a diameter of 20 cm (radius of 10 cm). Through the central point draw a straight line. Then draw the second line perpendicular to it. The same can be executed by means of a protractor or a direct triangle. As a result the circle will be divided into 4 equal parts. Further divide each of segments into 2 parts. For this purpose it is also possible to use a protractor, measuring 45 ° or a rectangular triangle which apply an acute angle in 45 ° and carry out beams. From the center on each straight line measure 10 cm. As a result 8 "rays" which connect among themselves will turn out. As a result the octagon will turn out.
4. Way 3. For this purpose also draw a circle, draw a line through the middle. Then take a protractor, put it on the center and measure corners, considering that each segment of an octagon has in the center a corner 45 °. After that on the received beams measure length 10 cm and connect them among themselves. The octagon is ready.