Please explain/show work: perpendicular lines,....... very confused?

L passes (2,2) and perpendicular y=3x+7

L passes (-1,-2) and perpendcular 2y-3x=12

3 Answers

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  • Mike
    Lv 5
    8 years ago
    Best Answer

    If L is perpendiculat to y = 3x + 7, it means the slope of L is a negative reciprocal of the slope of y = 3x + 7.

    The slope of y = 3x + 7 is 3, so the slope of L must is m = -1/3

    We are given a point (2, 2) with slope m = -1/3. Use the point-slope formula:

    y - 2 = -1/3(x - 2)

    y - 2 = (-1/3)x + 2/3

    y = (-1/3)x + 2/3 + 2

    y = (-1/3)x + 8/3

    For the second one, you need to find the slope of 2y - 3x = 12. To do this, solve for y.

    2y - 3x = 12

    2y = 3x + 12

    y = (3/2)x + 6

    So, L will have the slope m = -2/3. It passes through (-1, -2), so we use the point-slope formula again.

    y - - 2 = -2/3(x - - 1)

    y + 2 = -2/3(x + 1)

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

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

    y = (-2/3)x - 8/3

  • Anonymous
    8 years ago

    m is opposite and recipocal so 3 is -1/3 than solve for b. As in 2= -1/3(2)+b. The answer then is y=-1/3x+1.33333......with the little slash over the 3.

    2) so get that into y=mx+b form. y=3/2x+6. the opposite recipocal is -2/3. solve--------- -2=-2/3(-1)+b

    you then have the answer of y=-2/3x=2.6666666......with the little slash over the 6

    Source(s): my head, pencil, and paper
  • Anonymous
    8 years ago

    more specific?

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