Geometric Shapes: The Basics
by Colleen Wagner
1. Regular Octagon: Polygon with eight sides of equal length.
1.1. This stop sign is an example of a regular octagon.
2. Regular Decagon: A polygon with ten sides of equal length.
2.1. This is an example of a regular decagon.
3. Quadrilaterals: A geometric shape with four sides and angles.
3.1. Parallelogram: Quadrilateral with opposite sides parallel.
3.1.1. The U.S. flag is an example of a parallelogram.
3.2. Trapezoid: Quadrilateral that has at least one pair of parallel sides.
3.2.1. This is an example of a trapezoid.
3.3. Kite: Quadrilateral with two distinct pairs of congruent adjacent lengths.
3.3.1. The kites we played with as children is a great example.
3.4. Square: Rhombus with a right angle.
3.4.1. This Rubik's Cube is an example of many squares.
3.5. Rhombus: Quadrilateral where all sides have equal length.
3.5.1. This is an example of a rhombus.
4. Triangles: Polygon with three sides and three interior angles.
4.1. Equilaterial Triangle: Polygon in which all three sides and three angles are congruent.
4.1.1. This crossing sign is an equilateral triangle.
4.2. Isosceles Triangle: Polygon where only two sides and two angles are congruent.
4.2.1. The roof of this house is an isosceles triangle.
4.3. Right Triangle: Polygon that has exactly one right angle.
4.3.1. This is an example of a right triangle.