Geometry (.; geo means earth and metria "measurement") is a branch of mathematics concerned with questions of shape, size, relative position of figures, and the properties of space. A mathematician who works in the field of geometry is called a geometer.
PointPoint An exact location in space. It has no length, no breadth and no height. It has position and location but no magnitudes.
LineLine An endless collection of points along a straight path. The word ‘line’ usually refers to a ‘straight line’. A line has no width. It has length only. It is absolutely straight and can extend indefinitely in both directions.
Line segmentLine segment Part of a line that has two endpoints. The part of a line with two definite end points is called line segment
RayRayPart of a line that has one endpoint and extendsendlessly in the other direction
PlanePlaneAn endless, flat surface that is named by more than twopoints not on the same line.
Parallel LinesParallel Lines Lines do not intersect but are in the same plane . Linesare parallel if they lie in the same plane, and are thesame distance apart over their entire length
Intersecting LinesIntersecting Lines Lines meet at one point. Two lines are calledintersecting lines if they have a common pointthe common point is called the point of intersection.
Lines form a right angle. A line is perpendicular toanother if it meets or crosses it at right angles (90°).Perpendicular LinesPerpendicular Lines
AnglesAnglesAn angle is formed when two rays have thesame endpoint.This endpoint is called the vertex.The two rays that form the angle are calledsides.
There are four types of angles Right angle Straight angle Acute angle Obtuse angle
Right angle A right angle is an internal angle which is equalto 90°.
Straight AngleStraight Angle If an angle’s measure is 180°, it is called a straight angle.Straight angles are just lines with three points on them.
Acute Angles An acute angle is an angle whose measure is lessthan 90°. For these kinds of angles, a square could notfit perfectly at the intersection of the two lines that formthem.
Obtuse Angles An Obtuse Angle is more than 90° but less than 180°
ReviewReviewName each pictureName each picture Ray Parallel lines Line1.2.3.
ReviewReviewName each pictureName each picture Acute angle Line segment Point5.
ReviewReviewName each pictureName each picture Intersecting lines Perpendicular andIntersecting lines Plane