One hypothesis about the shape of the universe is that the universe is in the space of Euclidean geometry and flat. In Euclidean geometry, it is assumed that straight lines extend everywhere, planes ...

Everyone learns the number one rule about triangles in high school: the angles of a triangle add up to 180 degrees. But did you know that sometimes they don't? Triangles are much more interesting than ...

When a shape is enlarged, the image is similar to the original shape. It is the same shape but a different size. These two shapes are similar as they are both rectangles but one is an enlargement of ...

A scalene triangle has 3 sides of different lengths and 3 unequal angles. An isosceles triangle has 2 sides of equal length. The dashes on the lines show they are equal in length. The angles at the ...