Measuring an angle with a protractor
![The vertex of the angle is set at the zero point of the vertex.](https://peda.net/qis/2022-2023/mathematics/ematematiikka-722/o2kljpa/3-kulmia/ksmp/7_3_teoria4-png:file/photo/6950cd0b15fc077a1f4166d5f97e77dbb807171d/3_measuring-angles.png)
Example 1
Measure the degree of the angle [[$\beta$]] .This angle is an example of a convex angle, the degree of which cannot be measured directly with a protractor. First, measure the proportion of the acute angle that is missing from the full angle. Subtracting this from 360 ° gives the angle asked.
![7_3_esimerkki2.png](https://peda.net/qis/2022-2023/mathematics/ematematiikka-722/o2kljpa/3-kulmia/ksmp/7_3_esimerkki2-png:file/photo/5cb41779d58a8ad567fdf4181fe028449482902f/3_esimerkki1_taitto.png)
An angle bisectoris a ray that divides the angle into two equal parts.
Bisecting an angle with a protractor
An angle can be bisected with the help of a protractor.
![Bisecting an angle with a protractor](https://peda.net/qis/2022-2023/mathematics/ematematiikka-722/o2kljpa/3-kulmia/ksmp/7_3_teoria5-png:file/photo/3ec4a31bff69c8556d9e92a2f928ec21d568d1e9/3_bisecting-angles-protractor.png)