Lines and angles
Download
1 / 7

Lines and Angles - PowerPoint PPT Presentation


  • 273 Views
  • Updated On :

Lines and Angles . Geometry Chapter 3, Section 1. Notes . What does it mean for two lines to be parallel? Parallel lines: Lines that do not intersect and are coplanar . What about lines that don’t intersect and aren’t coplanar?

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Lines and Angles' - lotus


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Lines and angles l.jpg

Lines and Angles

Geometry

Chapter 3, Section 1


Notes l.jpg
Notes

  • What does it mean for two lines to be parallel?

    • Parallel lines: Lines that do not intersect and are coplanar.

  • What about lines that don’t intersect and aren’t coplanar?

    • Skew Lines: Lines that do not intersect and are not coplanar.

  • What does it mean for two planes to be parallel?

    • Parallel Planes:planes that do not intersect.

    • Example: the planes containing the ceiling and floor are parallel


  • Notes3 l.jpg
    Notes

    • Parallel Postulate:

      • If there is a line and a point not on the line, then there is exactly one line through the point parallel to the given line.

        • Parallel lines have the same slope (e.g. slope of 3 and 3)

        • Tilted at the same angle

    • Perpendicular Postulate:

      • If there is a line and a point not on the line, then there is exactly one line through the point perpendicular to the given line.

        • Perpendicular lines have slopes that are negative reciprocals (e.g. 4 and – 1/4)

        • At 90 degrees from each other


    Notes4 l.jpg
    Notes

    • Transversal: a line that intersects two or

      more lines in a plane at different points.

      • E.g. Line c is a transversal to lines a and b.

      • Line b is a transversal to which two other lines?

        • a & c

      • How about line a?

        • b & c

      • When a transversal

        intersects two lines,

        how many angles are

        formed?

        • 8 angles are formed


    Notes5 l.jpg
    Notes

    • Angles formed by a transversal.

      • We give certain pairs of these angles special names.

      • Corresponding Angles: 1 & 5 ; 2 & 6 ; 3 & 7 ; 4 & 8

      • Exterior Angles: 1, 2, 7, & 8

      • Interior Angles: 3, 4, 5, 6

      • Alternate Exterior Angles: 1 & 7 ; 2 & 8

      • Alternate Interior Angles: 3 & 5 ; 4 & 6

      • Consecutive Interior Angles: 4 & 5 ; 3 & 6


    Notes6 l.jpg
    Notes

    • Symbols for parallel in statements and figures

      • The symbol ll means is parallel to

      • The pink arrows on lines PQ and RS indicate that they are parallel.


    Angle pair names activity l.jpg
    Angle Pair Names Activity

    • Using about ¼ of a piece of binder paper, draw three lines so that one intersects two of the others.

      • Color the exterior angles all one color

      • Color the interior angles all one color

      • Label the exterior and interior angles

    • Using another ¼ of a piece of binder paper, draw three lines so that one intersects two of the others.

      • Color each pair of corresponding angles a different color.

      • Label this quarter sheet of paper “corresponding angles.”

    • Using another ¼ of a piece of binder paper, draw three lines so that one intersects two of the others.

      • Color each pair of alternate exterior angles a different color.

      • Color each pair of alternate interior angles a different color.

      • Label this quarter sheet “alternate exterior and interior angles.”

    • Using the final ¼ of a piece of binder paper, draw three lines so that one intersects two of the others.

      • Color each pair of consecutive interior angles a different color.

      • Label this quarter sheet “consecutive interior angles.