The humble triangle has been with us from the ancient pyramids to the modern days, being one of the most recognizable, interesting, and useful shapes in geometry. Ancient mathematicians laid the ...

Interior angles in a triangle add up to 180˚. Triangles close triangleA polygon with three straight sides. have three sides, therefore they have three angles. Interior angles in a triangle sum to a ...

Well, what is the best way to cut a sandwich in half? Surely triangles don't really have "more sandwich," right? That's geometry and the law of conservation of matter. But something about the ...

[Vintage VHS] Math Made Easy: Quick Geometry, Geometric Terms, Angles, Triangles, Parallelograms, Circles ...