Geometry


 * Geometry is one of the oldest sciences. Initially a body of practical knowledge concerning lengths, areas, and volumes, in the 3rd century BC geometry was put into an axiomatic form by Euclid, whose treatment—Euclidean geometry—set a standard for many centuries to follow. The field of astronomy, especially mapping the positions of the stars and planets on the celestial sphere, served as an important source of geometric problems during the next one and a half millennia. A mathematician who works in the field of geometry is called a geometer. "Earth-measuring" is a part of mathematics concerned with questions of size, shape, relative position of figures, and the properties of space.**

** Geometry Terms and Definitions **


 * Point - A location in space - a dot on a piece of paper.

Line - Connects two points via the shortest path and continues indefinitely (forever) in both directions.

Line Segment - Part of a line between two points.

Perpendicular Line Segment - Line Segments that intersect (cross) at an angle of 90°.

Parallel Line Segments - Line segments that never intersect (they are always the same distance apart).

Right Angle - An angle that measures 90°.

Acute Angle - An angle that measures less than 90°.

Obtuse Angle - An angle that measures more than 90°.

Vertex - Point at which two line segments intersect (forming an angle).

Scalene Triangle - A triangle with all three sides with different lengths.

Isosceles Triangle - A triangle with two equal length sides (and two equal internal angles).

Equilateral Triangle - A triangle with all three sides of equal length (each internal angles = 60°).**