slope formula

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slope formula

by Azizakaria » Thu Jan 28, 2016 11:17 am
Hello,

i study from MGMAT and Veritas and there's a difference in the slope formula between the 2 books so which is right?


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in Veritas


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by DavidG@VeritasPrep » Thu Jan 28, 2016 11:41 am
Azizakaria wrote:Hello,

i study from MGMAT and Veritas and there's a difference in the slope formula between the 2 books so which is right?


in MGMAT

Image

in Veritas


Image
It's the same formula. You can think of y2 - y1 as the rise. (The change in y represents the vertical change, or rise.)
And you can think of x2 - x1 as the run. (The change in x represents the horizontal change, or run.)

(And it doesn't matter which coordinates you designate y2 and y1, and x2 and x1, so long as you're consistent. For example. If you want the slope of the line that runs through (1,2) and (5, 7)
(7-2)/(5-1) will give the same result as (2-7)/(1-5)
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