In our mind’s eye, the universe seems to go on forever. But using geometry we can explore a variety of three-dimensional shapes that offer alternatives to “ordinary” infinite space. When you gaze out ...

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 ...

Trigonometry close trigonometryThe study of sides and angles in triangles. can be used to find a missing angle in a right-angled triangle when two sides are known. An understanding of the three ...

Discusses the properties and types of triangles, explaining that a triangle is a closed figure with three sides and angles. It categorizes triangles into equilateral, isosceles, scalene, obtuse, right ...

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 which are equal in length.) The angles at the ...