Context: A regular octagon is a closed figure with sides of the same length and internal angles of the same size. It has eight lines of reflective symmetry and rotational symmetry of order 8. A regular octagon is represented by the Schläfli symbol (8). The internal angle at each vertex of a regular octagon is 135 ° (3 π 4 ( \ displaystyle \ scriptstyle ( \ frac ( 3 \ pi) (4) ) ) radians ). The central angle is 45 ° (π 4 ( \ displaystyle \ scriptstyle ( \ frac ( \ pi) (4) ) ) radians ).

Question: how many lines of symmetry in an octogon?
Steam of consciousness below:

To answer the question, consider the following: It has eight lines of reflective symmetry and rotational symmetry of order 8.
So, the answer is eight.