SOLUTION: Find the slope of the line containing the given pair of points: (-13,22) and (8,-17)

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Question 604063: Find the slope of the line containing the given pair of points: (-13,22) and (8,-17)
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

First let's find the slope of the line through the points and


Note: is the first point . So this means that x%5B1%5D=-13 and y%5B1%5D=22.
Also, is the second point . So this means that x%5B2%5D=8 and y%5B2%5D=-17.


m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29 Start with the slope formula.


m=%28-17-22%29%2F%288--13%29 Plug in y%5B2%5D=-17, y%5B1%5D=22, x%5B2%5D=8, and x%5B1%5D=-13


m=%28-39%29%2F%288--13%29 Subtract 22 from -17 to get -39


m=%28-39%29%2F%2821%29 Subtract -13 from 8 to get 21


m=-13%2F7 Reduce


So the slope of the line that goes through the points and is m=-13%2F7


Now let's use the point slope formula:


y-y%5B1%5D=m%28x-x%5B1%5D%29 Start with the point slope formula


y-22=%28-13%2F7%29%28x--13%29 Plug in m=-13%2F7, x%5B1%5D=-13, and y%5B1%5D=22


y-22=%28-13%2F7%29%28x%2B13%29 Rewrite x--13 as x%2B13


y-22=%28-13%2F7%29x%2B%28-13%2F7%29%2813%29 Distribute


y-22=%28-13%2F7%29x-169%2F7 Multiply


y=%28-13%2F7%29x-169%2F7%2B22 Add 22 to both sides.


y=%28-13%2F7%29x-15%2F7 Combine like terms. note: If you need help with fractions, check out this solver.


So the equation that goes through the points and is y=%28-13%2F7%29x-15%2F7