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Line j has a slope of -7/8. Line k is perpendicular to line j. What is the slope of...

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greypeach | Student, College Freshman | (Level 3) eNoter

Posted August 28, 2011 at 8:54 PM via web

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Line j has a slope of -7/8. Line k is perpendicular to line j. What is the slope of line k?

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giorgiana1976 | College Teacher | (Level 3) Valedictorian

Posted August 28, 2011 at 8:58 PM (Answer #1)

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The product of the slopes of two perpendicular lines is -1.

We'll note the slope of the line j as `m_j` and the slope of the line k as `m_k` .

We'll compute the product of the slopes:

`m_(j)*m_(k) = -1`

`(-7/8)*m_(k) = -1`

`m_(k) = -1/(-7/8)`

`m_(k) = 8/7`

Therefore, the slope of the perpendicular line k is `m_(k) = 8/7` .

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vardhman1996 | Student, Grade 10 | (Level 1) Honors

Posted August 29, 2011 at 1:10 AM (Answer #2)

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Line J m=-7/8

Formula of slope of line perpendicular or another line is:

m1m2=-1     where m1 is slope 1 and m2 is the slope we have to find

therefore -7/8(m2)=-1

Take 8 on the other side as numerator and multiply by -1 take -7 as numerator therefore both the subtraction signs get cancelled.

therefore 8/7 is the slope of the K.

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sh953 | (Level 1) eNoter

Posted August 28, 2011 at 9:14 PM (Answer #3)

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The slope of a line is always the negitave reciprocal of the slope of the line perpendicular to it.

Therefore, the slope of line k is 8/7

 

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