1. Trapezoid - A trapezoid is a quadrilateral with one pair of opposite sides parallel. It can have right angles (a right trapezoid), and it can have congruent sides (isosceles), but those are not required.
2. Rhombus- Rhombus is a special type of a parallelogram whose all sides are equal. The difference between a square and rhombus is that all angles of a square are right angles, but the angles of a rhombus need not be right angles. So, a rhombus with right angles becomes a square.
3. Heptagon- A heptagon is a seven-sided polygon. It is also sometimes called a septagon, though this usage mixes a Latin prefix sept- (derived from septua-, meaning "seven") with the Greek suffix -gon (from gonia, meaning "angle"), and is therefore not recommended. 4. Concave - A concave polygon is a polygon that is not convex. A simple polygon is concave iff at least one of its internal angles is greater than. . An example of a non-simple (self-intersecting) polygon is a star polygon. A concave polygon must have at least four sides.
5. Hexagon- In geometry, a hexagon can be defined as a polygon with six sides. The two-dimensional shape has 6 sides, 6 vertices and 6 angles. We can find the shape of a hexagon in a honeycomb and a football, around us.
