Points, lines, line segments, and rays

Points, lines, line segments, and rays

In this lesson, we will learn:


Notes:

  • Points, Lines, Line Segments and Rays are basic figures in math that can be used to construct more complicated figures (i.e. angles, shapes, parallel/perpendicular lines, etc.)
Points, Lines, Line Segments and Ra

  • A point is a dot with position but no size nor shape (undefined) \,Points, Lines, Line Segments and Ra
    • There are an infinite number of points in figures (i.e. you can draw many points between endpoints in a line segment) \, Points, Lines, Line Segments and Ra
    • The proper notation of a point is just to write the named letter (ex. point AA)

  • A line has no beginning/end; an ongoing straight path of points Points, Lines, Line Segments and Ra
    • The arrows on both sides mean that it can extend infinitely in that direction
    • The proper notation of a line is to write the letters of two points in the figure and draw a double-sided arrow above the letters (ex. line AB\overleftrightarrow{AB})

  • A line segment is a part of a line with two finite endpoints Points, Lines, Line Segments and Ra
    • A line has arrows on both ends whereas the line segment has endpoints on both ends; the line continues forever, where the line segment ends where it is drawn
    • The proper notation of a line segment is to write the letters of the two endpoints and draw a bar above the letters (ex. line segment AB\overline{AB})

  • A ray starts at one endpoint and extends in one direction Points, Lines, Line Segments and Ra
    • One end of the ray has a point, whereas the other end of the ray has an arrow
    • The proper notation of a ray is to write the letters of two points in the figure (starting with the letter of the endpoint) and draw a one-sided arrow above the letters (ex. ray AB \overrightarrow{AB} )

Lessons

  • Introduction
    Introduction to Points, Lines, Line Segments and Rays:
    a)
    Introduction to basic figures and points

    b)
    What are lines?

    c)
    What are line segments?

    d)
    What are rays?

    e)
    Review of points, lines, line segments and rays


  • 1.
    Identifying lines, line segments, and rays
    Name the figure that is made by points AA and BB as either: a line, a line segment, or a ray.
    a)
    Points, Lines, Line Segments and Ra

    b)
    Points, Lines, Line Segments and Ra

    c)
    Points, Lines, Line Segments and Ra

    d)
    Points, Lines, Line Segments and Ra

    e)
    Points, Lines, Line Segments and Ra


  • 2.
    Proper notation for lines, line segments and rays
    Use proper notation (with letters and symbols) to name the figure
    a)
    Points, Lines, Line Segments and Ra

    b)
    Points, Lines, Line Segments and Ra

    c)
    Points, Lines, Line Segments and Ra


  • 3.
    Drawing lines, line segments and rays
    Draw the figure:
    a)
    ray MN\overrightarrow{MN}

    b)
    line segment QR\overline{QR}

    c)
    line GH \overleftrightarrow{GH}


  • 4.
    Combinations of lines, line segments and rays
    Name all the lines, line segments, and/or rays in the picture. Use proper notation.
    a)
    Points, Lines, Line Segments and Ra

    b)
    Points, Lines, Line Segments and Ra

    c)
    Points, Lines, Line Segments and Ra


  • 5.
    Intersecting lines, line segments and rays
    Connect the dots to draw the figures as indicated. Will the figure intersect? Yes or No.
    a)
    XW\overrightarrow{XW} and YZ\overleftrightarrow{YZ}

    Points, Lines, Line Segments and Ra

    b)
    AB\overline{AB} and DC\overrightarrow{DC}

    Points, Lines, Line Segments and Ra

    c)
    NO\overline{NO} and PQ\overrightarrow{PQ}

    Points, Lines, Line Segments and Ra

    d)
    RS\overline{RS} and TU\overleftrightarrow{TU}

    Points, Lines, Line Segments and Ra