Answer:
Step-by-step explanation:
Here is a diagram of a seven sided regular polygon. You use this diagram to find out how many degrees total are in the interior of a the heptagon. There are 5 such triangles which means that since each triangle has 180o the total amount of the interior angles must be 5 * 180 = 900
Since there are 7 interior angles, the answer to how large each one of them is is found by
900/7 = 129.57 which is slightly off because it is a rounded error.
In general, the size of the angles in a regular polygon
180(n - 2 ) / n
Where n is the number of degrees in each interior angle. For example for an 8 sided figure you would get
180(8 - 2) / 8 = 180 * 6/8 = 133 degrees.