Whenever we use the symbol ∠, we know that it is referring to an angle. One way to name an angle is to use the letter or number that corresponds to the vertex of the angle. In this case, it is P.
∠ P
However, in the exercise we have multiple angles with the same vertex, so we have to a use different notation.
To avoid confusion, we can place the letter name of the vertex between the name of points that lie on the rays creating the angle, PC and PR.
Because we have two other points lying on PR, point Q and point B, we can choose any one of them instead of R to create other names for our angle.
∠ CPQ or ∠ CPB
We can also reverse the order of letters in each name. This means that ∠ QPC, ∠ BPC, and ∠ RPC are also valid names for angle ∠ CPR. We can choose any pair of them for our answer.
