91Ó°ÊÓ

The theorem for the sum of interior angles for convex polygon states that the sum of measures of the interior angles of a convex polygon with sides is $\left(n-2\right)180$.

The number of sides in a Octagon is 8.

Therefore, the value of$n$ is 8.

By using the theorem for the sum of interior angles for convex polygon, the sum of the interior angles for the polygon having 8 sides is given by:

$$\begin{gathered} \left(8−2\right)180=6×180 \\ =1080 \end{gathered}$$

Therefore, the sum of interior angles for the Octagon is $1080°$.

The theorem for the sum of exterior angles for convex polygon states that the sum of measures of the exterior angles of a convex polygon is $360°$.

The number of sides in a Octagon is 8.

Therefore, the value of$n$ is 8.

By using the theorem for the sum of exterior angles for convex polygon, the sum of the exterior angles for the polygon having 8 sides is $360°$.

Therefore, the sum of exterior angles of the Octagon is $360°$.