What is a hexagon? Simple geometry
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 [...]
29
07, 2017
29
07, 2017
Checking the surface area of a sphere
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 [...]
29
07, 2017
Volume of a cone – Geometry
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 [...]
28
07, 2017
Proof for the area of a circle
Proof for the area of a circle: Divide a circle up into sections like an orange Euclid's proof We know it's true that A=πr-squared is the area of a circle, but how can we prove [...]
28
07, 2017
Definition of a circle – Geometry
A circle is the set of points on a plane that are all the same distance away from a center point. A circle is the set of points on a plane that are all [...]
28
07, 2017
Area of a triangle – Geometry
Area of a triangle To figure out the area of a triangle, multiply the base by the height of the triangle, and then divide by two: (Base x Height)/2. That's because the height [...]
28
07, 2017
Area of an oval – Geometry
Area of an oval The area of an oval is the part of a plane that is inside its circumference. To figure out the area, you need to measure the height and width of the oval. [...]
28
07, 2017
Area of a circle – Geometry
The geometry of a circle The area of a circle is the flat surface inside its circumference. The area is always equal to the radius squared, multiplied by π (pi). Here's a proof that [...]
7
06, 2017
What are the Nine Chapters? Math in Ancient China
Nine Chapters: How to figure out the area of an isosceles triangle. A math textbook from Han Dynasty China The earliest Chinese mathematical textbook is called the Nine Chapters. It [...]
