What is a triangle? Simple geometry
This is an equilateral triangle. A triangle is any set of three points on a plane and the lines connecting those points to each other, as long as the three points aren't all on the [...]
This is an equilateral triangle. A triangle is any set of three points on a plane and the lines connecting those points to each other, as long as the three points aren't all on the [...]
This is a trapezoid. A trapezoid is a kind of quadrilateral that has at least two sides that are parallel to each other. A parallelogram is a trapezoid that has two pairs of parallel [...]
This is a right triangle, because one of the angles is a right angle. A right triangle is any triangle where one of the angles is exactly 90 degrees, or a right angle. You [...]
This is a rhombus, divided so you can figure out the area. A rhombus is a kind of quadrilateral that has two sides that are parallel to each other, and another two sides that [...]
This is a rectangle. A rectangle is a flat shape, in one plane. It's defined by four points at the four corners. A rectangle has two sides of equal length opposite each other, [...]
This is a triangular prism A prism is the solid shape you get if you move a flat polygon through space. A prism has five planes: a top, a bottom, and [...]
What is pi? The geometry of a circle What is pi? Pi is a number that is just a little bigger than 3.14. It is the number you get if you divide [...]
The perimeter of this rectangle is in dark green. The perimeter of a square or a triangle is the distance all the way around the edge - the green strip in this picture. The circumference 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 [...]