Summary

(1) A point determines a locationplace. It is denoted by a capital letter.

(2) A line segment corresponds to the shortestlinear distance between two points. The line segment joining points S and T is denoted by ST.

(3) A line is obtained when a line segment like ST is extended on both sides indefinitelyupto a point ; it is denoted by ST or sometimes by a single small letter like m.

(4) A ray is a portion of a line starting at a point D and going in one direction indefinitelyupto a point. It is denoted by DP where P is another point on the ray.

(5) An angle can be visualised as two (s) starting from a starting point. _{span.reveal(when="blank-5")}Two rays OP and OM form the angle ∠POM (also called ∠MOP); here, O is called the of the angle, and the rays OP and OM are called the (s) of the angle._

(6) The size of an angle is the amount of or turn needed about the vertex to rotate one ray of the angle onto the other ray of the angle.

(7) The sizes of angles can be measured in (s). One full rotation or turn is considered as degrees and denoted as 360°.

(8) Degree measures of angles can be measured using a .

(9) Angles can be (180°), (90°), (more than 0° and less than 90°), (more than 90° and less than 180°), and (more than 180° and less than 360°).