Writing an equation for a line perpendicular and through a point

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Taught by mrbrianmclogan
  • Currently 4.0/5 Stars.
8049 views | 1 rating
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Lesson Summary:

In this lesson, you will learn how to find the equation of a line that is perpendicular to a given line and passes through a given point. The key to this is knowing that perpendicular lines have opposite reciprocal slopes. By finding the opposite reciprocal slope of the given line, you can then use the slope-intercept method to write the equation of the perpendicular line. This method involves plugging in the given point and the new slope to find the equation in the form y=mx+b. Understanding this concept will enable you to easily write equations for lines that are perpendicular to a given line.

Lesson Description:

Writing an equation for a line that is perpendicular to a given line and goes through a given point.

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Questions answered by this video:
  • How do you write an equation for a line that is perpendicular to a given line and goes through a given point?
  • How do you find the equation of a line perpendicular to y = 3/8x - 3 that passes through (4, -10)?
  • What is the slope of a perpendicular line?
  • What is the slope of the line perpendicular to y = 3/8x - 3?
  • How do you find the y-intercept of a line if you know the slope and a point?
  • Staff Review

    • Currently 4.0/5 Stars.
    This lesson shows an example problem of writing an equation for a line that is perpendicular to a given line that passes through a given point. First, the idea of finding the slope of a line perpendicular to a given line is explained. Then, the y-intercept is found for the new line. Unfortunately, the end of the y-intercept calculation is cut off of the screen. But all steps are explained well.