Basic Shapes Identification and Analysis Workbook-1
Basic Shapes Identification and Analysis Workbook-2
Basic Concepts of Geometry Workbook-1
Angles: When two straight lines meet at a point they form an angle. In the figure, the angle is represented as ∠AOB. OA and OB are the arms of ∠AOB. Point O is the vertex of ∠AOB. The amount of turning from one arm (OA) to other (OB) is called the measure of the angle (AOB).
Right angle: An angle whose measure is 90o is called a right angle. ∠ BOA is a right angle in the figure.
Acute angle: An angle whose measure is less then one right angle (i.e., less than 90o), is called an acute angle.
Obtuse angle: An angle whose measure is more than one right angle i. e. 90o and less than two right angles
(i.e., less than 180o and more than 90o) is called an obtuse angle.