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Math Help - on the slope of line

  1. #1
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    on the slope of line

    Practice Write the equation of the line that passes through the given point and is perpendicular to the given line. Write the answer in slope-intercept form.
    P(-3, 3), y + 9x = -15

    i did the whole y-y1=mx(x-x1)
    and i came up with y-3=-1/9x[x-(-3)]
    = y-3=-1/9(x+3)
    =9y-27=-x-3
    =9y=-1/9x+8/3

    What am I doing wrong? PLEASE HELP
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  2. #2
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    What am I doing wrong?
    y + 9x = -15

    y = -9x - 15

    the slope of this line is m = -9. the perpendicular slope is \frac{1}{9}

    using the slope m = \frac{1}{9} and the point (-3, 3) ...

    y - 3 = \frac{1}{9}(x + 3)

    y - 3 = \frac{1}{9}x + \frac{1}{3}

    y = \frac{1}{9}x + \frac{10}{3}
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