It is enough to take usual school supplies – a pencil and paper, a ruler, a protractor and compasses – and it is possible to draw any geometrical figure, whether it be a square, an oval, a triangle. However there are cases when there are no drawing tools near at hand at all or their quantity is limited, but even in this case it is possible to make the necessary drawing.
It is required to you
- - ruler;
- - pencil;
- - paper;
- - compasses;
- - protractor;
- - rectangular triangles
Instruction
1. If near at hand there is nothing except the sheet of paper and a pencil, then it is possible to manage even these accessories. For this purpose very accurately curtail the sheet of paper four times, at the same time well smoothing down bends. As a result on the place of a double bend receive a right angle which has 90 °. Put a corner once again in half, and the required corner in 45 ° will turn out. The truth in this case will be shown a small error in the form of loss of several degrees. For more exact drawing circle a right angle with a pencil on a clean sheet of paper, accurately cut out it and put in half – it will give a corner in 45 °.
2. It is possible to draw a corner by means of rectangular triangles which can be different – with corners 90 °, 45 °, 45 ° and 90 °, 60 °, 30 °. Take a triangle (with corners 90 °, 45 °, 45 °) and circle on the sheet of paper an acute angle in 45 °. If there is only a triangle with corners 90 °, 60 °, 30 °, then on other sheet of paper circle a right angle, cut out it, put in half and circle on the necessary drawing. It will also be a corner in 45 °.
3. The option of construction at which the protractor is used will be the most exact. Draw the line on the sheet of paper, note on it an angular point, apply a protractor and note a point 45 ° then connect them among themselves.
4. It is interesting that even by means of compasses it is also possible to represent a corner in 45 °. For this purpose it is enough to have before itself the represented corner in 90 ° (for example, by means of a rectangular triangle or by paper bending four times). Then from an angular point carry out by compasses a circle. In the place of crossing of a circle and the parties of a right angle note points. Now from each of two points the same solution of compasses make two more circles. In the place of their crossing the point which connect to angular will turn out therefore two corners on 45 ° will turn out.