Observe the picture below:

m (AOC) = m (COB) = 20th

Verify that the straight splits the angle AÔB into two congruent angles (AÔC and COB). In this case, the semi-straight is called **bisector **from angle AÔB.

Like this:

**Bisector**One angle is the semi-straight one that originates at the vertex of that angle and divides it into two other congruent angles.

## Using the compass to construct the angle bisector

### Determination of angle bisector AÔB

We center the measure on O and with an opening we determine the points C and D on the straight respectively.

We center the bar on C and D and with an opening greater than half the distance from C to D we draw intersecting arcs on E.Let's draw , thus determining the bisector of AÔB.

Next: Acute, obtuse and right angle