It is an 8 sided polygon known as an octagon
A 5 sided shape with 5 angles is a pentagon
assuming you meant a pentagon (as i have never heard of a pentgon and neither has google), it is a two dimensional shape with five sides and five angles
It is a regular polygon.
Three-dimensional. It has height, width and depth.
A pyramid is a three-dimensional figure with five verticies and five sides (four of which are triangles and one of which is a square). A pentagon is a two-dimensional figure with five angles and five edges.
circle
A two-dimensional shape (polygon) is said to be "regular" (or equilateral) if all its sides are the same length and all its angles are the same angle. A regular pentagon, for example, has 72-degree angles on all five angles, and all its five sides are the same length.
A polygon; specifically a tetragon. A two-dimensional shape with four equal sides and four right angles is a square. A two-dimensional shape with two sets of equal sides and four right angles is a rectangle. A two-dimensional shape with two sets of equal sides and two sets of equal angles is a parallelogram. A parallelogram where each opposite angel bisects the shape is a rhombus. A two-dimensional shape with one set of equal, parallel sides and two sets of equal angles is a trapezoid. A three-dimensional shape with four triangular faces is a tetrahedron.
a heptagon
They are said to be irregular shapes or polygons
A two-dimensional shape with eight angles is called an octagon. An octagon has eight sides and eight vertices, with the most common example being a regular octagon, which has equal sides and angles. It can be found in various contexts, such as stop signs in traffic.
Squares and rectangles have a two-dimensional shape with four sides and four right angles.
Assuming it is a two dimensional shape, 12 sides implies 12 angles (interior or exterior).
A two-dimensional shape with eight angles is called an octagon. It has eight sides and eight vertices, and the sum of its interior angles is 1,080 degrees. Regular octagons have equal side lengths and angles, while irregular octagons can vary in shape. Common examples of octagons include stop signs and some tiles.
A 5 sided shape with 5 angles is a pentagon
If the shape has 3 angles in all, where two of the angles are acute, then the shape is a scalene triangle.
If the shape is two-dimensional then it is a circle, if the shape is three-dimensional then it's a sphere.