Introduction to Lines and Angles
Line Segment: A line with two end Points
Ray: a line with one end point.
Collinear points: If three or more points lie on the same line they are collinear.
Angle: The figure formed by two rays having a common end point.
Acute Angle: An angle whose measure is more than 0° and less than 90°.
Right Angle: An angle whose measure is equal to 90°.
Obtuse Angle: An angle whose measure is more than 90° and less than 180°.
Straight Angle: An angle whose measure is equal to 180°.
Reflex Angle: An angle whose measure is more than 180° and less than 360°.
Adjacent Angles: Two angles are said to be adjacent if they have common side and a common vertex.
Linear Pair of Angles: Two adjacent angles are said to be linear pair f their sum is 180°.
Vertically Opposite Angles: When two lines intersect, four angles are formed. The angles opposite each other re called vertically opposite angles and are equal.
Complimentary Angles: A pair of angles whose sum is 90°.
Supplementary Angles: A pair of angles whose sum is 180°.
Intersecting Lines: Lines that have one point in common Non-Intersecting Lines: Lines that do not have any point in common.
Parallel Lines
1. Construct the parallel line
2. Draw parallel lines using setsquare
3. Draw parallel lines using setsquare
4. Draw a line parallel to an inclined line