The highly technical term is "BLOB"!
An irregular shape!
A shape that does not have equal sides is called an irregular shape.
a quadrilateral
A shape with 9 unequal sides would be called an irregular nonagon or an irregular enneagon.
trapezoid
An irregular shape!
Irregular
An irregular hexagon.
It is an IRREGULAR shape.
Not surprisingly, it would be called an irregular galaxy.
A shape that does not have equal sides is called an irregular shape.
There is no formula. That's why it's called irregular!
An octagon. Or more specifically, an irregular octagon.
a quadrilateral
A shape with 9 unequal sides would be called an irregular nonagon or an irregular enneagon.
an irregular polygon
trapezoid