Geometry

Introduction to Geometry

Geometry is the section of mathematics that deals with properties, measurements, and construction of 2 dimensional and solid figures. The word "Geography" mean to the measure earth.

Basic concepts and figures.

• A Point

• A point is represented by a dot. A point has no length, width , or thickness. Think of a point only as a location in space. A point is always named with a capital letter.

Basic concepts and symbols

• A Line

• A Line extends infinitely in two opposite directions and are named by using two capital letters which are points on the line.

• Aline can also be named using one lowercase letter.

• Lines can be vertical, horizontal, or oblique (Slanting).

Basic concepts and symbols

• A Line Segment

• A line segment is a portion of a line that has two end points by which it is named.

• A line segment can also be horizontal, vertical, and oblique.

Basic concepts and symbols

• Ray

• A ray is a portion of a line that has one endpoint.

• Therefore, a ray extends in one direction infinitely but end at a point in the opposite direction.

• The first capital letter names the endpoint, and the second capital letter names a point of the ray.

Basic concepts and symbols

• Angles

• An angle is two rays that shares a common endpoint.

• The common endpoint is called the vertex, and the two rays are called the sides of the angle.

• There are several ways to name an angle. one capital letter can be used e.g. <B Other time three letters are used <ABC.

• When three capital letters are used the middle letter is always the vertex.

Basic concepts and symbols

• Intersecting Lines

• Intersecting lines are lines that has one point in common.

• Two lines can intersect at only one point.

Basic concepts and symbols

• Plane

• A Plane is a flat surface that extends infinitely in all directions

Basic concepts and symbols

• Parallel Lines

• Parallel lines are lines in the same plane that never intersects and has equal distance between them.