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Math Help - Find Value of k

  1. #1
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    Exclamation Find Value of k

    Find the value of k if the lines 3x-2y-5=0 and kx-6y+1=0 are parallel.

    3x-2y-5=0

    3x-5=2y

    \frac{3}{2}x-\frac{5}{2}=y

    m=\frac{3}{2}

    I found the slope of the parallel lines but have no idea how I would find k
    Can anyone help please? Thank you very much!
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  2. #2
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    Quote Originally Posted by larry21 View Post
    Find the value of k if the lines 3x-2y-5=0 and kx-6y+1=0 are parallel.

    3x-2y-5=0

    3x-5=2y

    \frac{3}{2}x-\frac{5}{2}=y

    m=\frac{3}{2}

    I found the slope of the parallel lines but have no idea how I would find k
    Can anyone help please? Thank you very much!
    Maybe from observing what you just did you can see that for the line

    Ax + By + C = 0

    the slope (assuming it's defined) is -A/B

    But you don't have to see this, you can just solve the second equation for y (thus putting it into slope-intercept form), see what the slope is (it will be in terms of k) and then set that to 3/2.
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  3. #3
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    So.....

    \frac{kx}{6}+\frac{1}{6}=y

    I don't get how this helps me?
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  4. #4
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    Quote Originally Posted by larry21 View Post
    So.....

    \frac{kx}{6}+\frac{1}{6}=y

    I don't get how this helps me?
    The lines are parallel, meaning they have the same slope. Write

    \frac{3}{2}=\frac{k}{6} and solve for k.
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