SOLUTION: find an equation of the line containing the given pair of points (-5,-3),(-9,-2).

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Question 600365: find an equation of the line containing the given pair of points (-5,-3),(-9,-2).
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


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


m=%28-2--3%29%2F%28-9--5%29 Plug in y%5B2%5D=-2, y%5B1%5D=-3, x%5B2%5D=-9, and x%5B1%5D=-5


m=%281%29%2F%28-9--5%29 Subtract -3 from -2 to get 1


m=%281%29%2F%28-4%29 Subtract -5 from -9 to get -4


m=-1%2F4 Reduce


So the slope of the line that goes through the points and is m=-1%2F4


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--3=%28-1%2F4%29%28x--5%29 Plug in m=-1%2F4, x%5B1%5D=-5, and y%5B1%5D=-3


y--3=%28-1%2F4%29%28x%2B5%29 Rewrite x--5 as x%2B5


y%2B3=%28-1%2F4%29%28x%2B5%29 Rewrite y--3 as y%2B3


y%2B3=%28-1%2F4%29x%2B%28-1%2F4%29%285%29 Distribute


y%2B3=%28-1%2F4%29x-5%2F4 Multiply


y=%28-1%2F4%29x-5%2F4-3 Subtract 3 from both sides.


y=%28-1%2F4%29x-17%2F4 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=%28-1%2F4%29x-17%2F4