Acute Triangle

All angles in the triangle are less than 90 degrees.

Obtuse Triangle

A triangle where one angle measures over 90 degrees.

Right Triangle

One angle in the triangle measures exactly 90 degrees.

Isosceles Triangle

A triangle with at least 2 congruent sides

Equilateral Triangle

All the sides of the triangle are equal in length

Scalene triangle

No equal sides

Kite

Quadrilateral with 2 pairs of adjacent congruent sides, with perpendicular diagnals

Square

A quadrilateral with 4 sides that are equal and has all 90 degree angles

Rhombus

A quadrilateral, all 4 sides the same length

Trapezoid hd

Quadrilateral in which exactly 1 pair of parallel sides

Trapezoid bd

A quadrilateral with at least 1 pair of parallel sides

Rectangle

A quadrilateral in which the opposite sides are parallel, all angles are 90 degrees

Parallelogram

Quadrilateral in which the opposite sides are parallel

Sphere

All points in a space that are a fixed distance away from a fixed poit

Circle

An infinite number of points connected around an equal distance from a middle point`

Polyhedron

(The plural is polyhedra) A three dimensional object whose surfaces are composed of polygonal regions (faces, verices, edges)

Convex polyhedron

is defined in a manner similar to that used in defining a convex polygon

Concave polyhedron

Is defined in a manner similar to that used in defining a concave polygon.

Convex Polyhedron

is defined in a manner similar to that used in defining a convex polygon

prism

a polyhedron that has two parallel faces that are congruent. These 2 faces are called the bases of the prism. The other faces of the prism are called the lateral faces. (right prism, oblique prism)

Pyramid

A polyhedron whose base is a polygon ad whose faces are triangles that have a common vertex. That common vertex is called the apex of the pyramid.

Regular Polyhedron

A convex polyhedron in which the faces are congruent regular polygons and in which the number of edges that meet at each vertex are the same.

Cylinder

A simple closed surface that is bounded by two congruent simple closed surfaces that lie in the parallel plane

Cone

A siple closed surface whose base is a simple closed surface and whose lateral surfaces slopes up to a vertex that is called the apex

Sphere

The set of all points in a three dimensional space that are the same distance from a fixed point, called the center