SOLUTION: do the given points lie in a straight line? (-2,2), (5,-8), (-7,9)

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Question 1045547: do the given points lie in a straight line? (-2,2), (5,-8), (-7,9)
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
Look at the slope between the first and second, and the second and the third. If they are in a straight line, the slopes will be equal.
-8-2/5-(-2)=-10/7=-1.43
9-(-8)/(-7-5)=17/-12. They aren't equal.=-1.42
As a check, look at the first and third.
(9-2)/(-7-(-2))=7/-5=-1.4
None of these is the same, although they are close. This isn't linear.
Here's a graph of the first and third points.
graph%28300%2C200%2C-10%2C10%2C-10%2C10%2C%28-7x%2F5%29-%284%2F5%29%29