# How to build a circle?

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Circumference - the perfect line, which is not always possible to draw exactly. For this there is a special device - compasses. It allows you to avoid mistakes and to build the circle perfectly and accurately. However, the compass is not always at hand.

Let's take a closer look at how to build a circle using and without compasses.

## How to build a circle with compasses

- First you need to decide on the radius of the future circle. It corresponds to the solution of our compass, that is, the distance between the divorced legs of compasses.
- Next, measure the radius itself. This can be done with a compass andrulers. For example, the radius of our circle is 3 cm. To measure it, put the leg of the compass at the beginning of the ruler and dilute it to the indicated length. This is the radius of the circle.
- After that you can start drawing a circle. Putting the leg of the compass with the needle tip on the paper, and measuring the length of the radius, slightly tilting the compass,make circular movements with the other leg of the compass. For a start, you can make a light pressure, and then circle the circle with a thicker layer. The circle is ready!

But you don't always have a compass. So how can you draw a circle with the help of available tools? Let us give some examples.

## How to build a circle without compass

Perhaps the easiest and most expensive way to do this is to enclose something round, be it a saucer, a clock, a coin or something else. But round items may also not be nearby.

Then you can try the second option, which everyone will be able to do. First you need to draw a square, and only then from it, by truncating the corners, draw a circle. Well, the third option, which can be used both on a blackboard with chalk and in a notebook with a pencil, is with the help of a thread. You can make an imitation of a compass and bind the thread to a pencil, measure also the required diameter and, putting a thread on the sheet, draw a circle, as is the case with a compass.