Step-by-step explanation:
It appears that given geometrical shape is a HEXA-DECAGON or a 16 sided polygon.
Measure of one interior angle of hexa-decagon can be given as:

Equation of a circle:
(x - h)^2 + (y - k)^2 = r^2
In this case:
<span>center (2,7) and radius 4 so h = 2, k = 7 and r = 4
</span>Equation:
(x - 2)^2 + (y - 7)^2 = 4^2
(x - 2)^2 + (y - 7)^2 = 16
Hope it helps.