This time it's about "angles and their sizes" that we learn in XNUMXth grade math.

**Content to explain!**

- What is the size of an angle
- How to measure angles (How to use a protractor XNUMX)
- How to draw angles (How to use a protractor XNUMX)

This is an explanation of angles that are the basis of various shapes such as quadrilaterals!

## angle and its size

the size of the angle**how far the line has turned**is determined by

The unit of the size of an angle is "degree (°)".

The first state is \(0°\).If you go straight up from there, \((90°)\)

It is \(180°\) when it goes to a straight line, and \(360°\) when it goes around.

A protractor can measure from \(0°\) to \(180°\)!

## How to measure angles (How to use a protractor XNUMX)

Now let's see how to measure the size of an angle.

You need a protractor to measure angles!

In the angle shown in the figure, side ①③ is on \(75\), so the size of this angle is \(75°\).

## How to draw angles (How to use a protractor XNUMX)

I checked the angle you mentioned earlier several times.

Next is how to decide the angle and write the angle.

This time I wrote an angle of \(75°\), but if you want to write an angle of \(120°\), it is OK if you type point ③ in the memory of \(120\).

If you can draw the corners in the size you want, you can use it when drawing triangles and quadrilaterals!

This time is over!

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