It was Archimedes.
Archimedes (287-212 BC) was the first to estimate π rigorously. He realized that its magnitude can be bounded from below and above by inscribing circles in regular polygons and calculating the outer and inner polygons' respective perimeters. By using the equivalent of 96-sided polygons, he proved that 310/71< π < 31/7. The average of these values is about 3.14185.
umm im noot 100% sure but i am pretty sure its pythagoras or euclid
One mathematician who made significant contributions to areas related to circles is Archimedes. He is known for his discovery of the relationship between the circumference and diameter of a circle, which is now known as π (pi). Archimedes also developed methods to approximate the area enclosed by a circle using polygons, a technique now known as the method of exhaustion.
no straight sides
yes. polygons are closed shapes with no curves. i.e. circles are not polygons, squares are, triangles are, ect
A circle is not a polygon, so no.
Circles and all regular polygons.
a polygon has all closed sides and no curved sides
They are closed 2-dimensional shapes.
There are 20.5 + 6 + 9 = 20 (Neither circles nor unclosed linear shapes are polygons.)
Circles, some triangles, and irregular polygons
A polygon is a two-dimensional shape enclosed by lines only, not curves. So triangles, squares, rectangles, and octagons are examples of polygons. Circles, ellipses, and annuli are some shapes that are not polygons.