Geometry: This is an equilateral trangle. What is geometry? The simplest geometric idea is the point, and then the line, the plane, and the solid. Shapes like circles, squares, rectangles, and triangles are flat, and we can think of [...]
This is an isosceles triangle. Definition of an isosceles triangle Isosceles triangles have at least two sides that are exactly the same length. This forces two of their angles to also be acute angles of exactly [...]
This is a hexagon. See, it has six sides that are all the same length. Definition of a hexagon A hexagon is a flat shape, all in one plane, with six [...]
This is an equilateral triangle. What makes a triangle equilateral? Equilateral triangles have all three sides exactly the same length. Because their sides are the same length, the three angles of an equilateral triangle are also [...]
Did you ever have to wrap a basketball as a present? To see how the surface area of a sphere is really 4πr2, find a ball to wrap (a basketball works well). Cut some [...]
A painting with bilateral symmetry - made using mirroring in a paint program To see what bilateral symmetry is, paint a picture. Take a sheet of paper and fold it [...]
The geometry of a circle The diameter of a circle is the distance across the circle at the widest part of the circle. The diameter is always equal to twice the radius of the [...]
This is a cylinder. What can you find around your house that's a cylinder? A cylinder is a circle moved through space to make a solid form. The ends are circles that [...]
Do you know how to do a Rubik's cube? A cube is a square moved through space, so it gets thicker. All cubes have six sides - the top, the bottom, and [...]
How much ice cream fits inside this cone? A cone is the set of all the line segments that start from one circle and go to a point not on the circle. You could think of [...]
