Families of Lines

Key Questions

  • A family of lines is a set of lines that have something in common with each other.

    In brief, we can have two types of families of lines:

    1. one where the slope is the same #-># keep the slope unchanged and vary the #y#-intercept #-># parallel lines
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    2. one where the #y#-intercept is the same #-># keep the #y#-intercept unchanged and vary the slope #-># concurrent lines
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  • All lines following a specific criteria are called a family of lines.

    For eg.
    If the criteria is passing through a point (0,0)
    Then all possible lines passing through that point are called the family of lines.

    If the criteria is have a slope of -1,
    Then all possible lines have slope = -1 are its family of lines.

    The idea is similar to human families where all our relatives belong to the same family (the criteria) and therefore everyone is a family member.

    I hope this helps.