If a shape is a regular pentagon with five sides what must be true

A pentagon is a closed 5 sided polygon.

A regular polygon has all sides equal as well as all angles equal.

°The formula to find the sum of all angles of a polygon is = (n-2) * 180

So for a pentagon, n = 5

So the sum of all the angles must be (5-2) * 180 = 3 * 180 = 540.

Now as it is a pentagon, it shall have 5 vertices.

So there are 5 angles in a pentagon and all must be equal.

Hence each interior angle must be 540/5 = 108

So for a regular polygon with 5 sides must have each interior angle = 108

Step-by-step explanation:

A) it is symmetrical

B) it has five lines of symmetry

C) it has reflectional symmetry