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Math Help - equation and slope of lines

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    Exclamation equation and slope of lines

    Find the equation of each line. Write each answer in slope intercept form.

    1.) The line goes through (1,2) and is perpendicular to y=1/2x-3



    2.) The line goes through (2,3) and is parallel to -2x+y=6
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    Quote Originally Posted by jsimms View Post
    Find the equation of each line. Write each answer in slope intercept form.

    1.) The line goes through (1,2) and is perpendicular to y=1/2x-3



    2.) The line goes through (2,3) and is parallel to -2x+y=6
    How are the slopes of perpendicular lines related.

    m_2=\frac{-1}{m_1}

    They are negative reciprocals

    the negative reciprocal of 1/2 is -2 or using the above formlua

    m_2=\frac{-1}{\frac{1}{2}}=-2

    now using the point and the slope we get

    y-2=-2(x-1) \iff y-2=-2x+2 \iff y=-2x+4

    If lines are parallel they have the same slope.

    Try putting the above line in y=mx+b form.

    I hope this helps.

    Good luck.
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    Parallel Lines have same slope

    In response to your second situation, note that parallel lines have the same slope.

    Therefore, -2x + y = 6 is equivalent to y = 2x + 6. The slope (m) = 2

    Use point-slope form again (y - y_1) = m(x - x_1) with (2, 3) and m = 2, we have:

    (y - 3) = 2(x - 2)

    You may want to convert this one to y =mx + b or ax + by = c.
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