2. ines and Angles By: Adrienne Hodge Arkansas State University adrienne.hodge@smail.astate.edu Site 2012

3. What is a Line?  A line continues forever in two directions.  The continuation is shown by arrows on each end of the line.

4. What is a Line Segment?  A line segment does not continue forever in two directions.  The endings to a line segment are usually shown in math by a dot on each end of the line.

5. What is a Ray?  A ray continues forever in only ONE direction.  The end that continues forever is shown by an arrow.

6. Parallel Lines  Lines in a plane that are always the same distance apart. These lines will NEVER intersect with each other.

7. Perpendicular Lines  Two lines intersect each other and create a 90˚ angle.

8. Skew Lines  Lines that are not in the same plane, are not parallel, and do not intersect.

9. Transversal Line  A line that crosses two or more lines. In most cases the lines it crosses create parallel lines.

10. What is a vertex?  When two rays come together to form an angle, the point at which they meet is called the vertex.

11. Right Angles  Have a 90° Angle  Are usually marked with a small square in the angle to identify it as a Right Angle

12. Acute Angle  An angle that measures less than 90°  It’s a cute little angle

13. Obtuse Angles  Angles that have a measure of more than 90˚