**Naming Angles**

Angles can be named in several ways. The simplest is to label the vertex with a single letter preceded by a slanting L:

When angles share sides we can place numbers inside (close to the vertex). For example, angles *1* and *2* share the common vertex *A*:

We also use little arcs centered at the vertex with tick-marks to indicate angles that have the same measure. Here angles *1* and *2* are equal (in measure):

You can also name an angle using three letters, where the middle letter is the vertex and the other two are points on the sides: