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Homework Help: Identifying the slope of a line

  1. Apr 20, 2016 #1
    1. The problem statement, all variables and given/known data
    identifying the slope of the line?


    2. Relevant equations

    3. The attempt at a solution
    i chose two points on the line, the first point is (8,-3) and the second point is (-6,4). Are these points accurate?
    i used the slope equation to solve for the slope of the line from the graph:
    4-(-3) / -6-8 = -7/14 = -1/2

    is this right?

  2. jcsd
  3. Apr 20, 2016 #2


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    Well done. One tip: use brackets -- not 4-(-3) / -6-8 but ( 4-(-3) ) / ( -6-8 )
  4. Apr 20, 2016 #3
    can the answer also be 7/-14 and 1/-2
  5. Apr 20, 2016 #4

    Ray Vickson

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    What you wrote means ##y_2 - \frac{y_1}{x_2} - x_2##, which is not correct. Did you mean ##\frac{y_2 - y_1}{x_2 - x_1}##? If so, you need to use parentheses, like this: (y2-y1)/(x2-x1).
  6. Apr 20, 2016 #5


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    Both of these are the same value as ##-{1\over 2}##, which is the simplest way to express that value. Whatever points you choose, you always get ## - {a\over 2a}## as a result.
  7. Apr 20, 2016 #6
    got it, thanks!
  8. Apr 20, 2016 #7
    its a straight line ,so where lies the confusion about its being wrong?
  9. Apr 20, 2016 #8
    i solved this question previously and got a different slope compared to what I'm getting now. Then i realized that my points were wrong when doing it the first time, so i wanted to make sure the points i chose were correct in my second attempt.
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