SOLUTION: Find an equation of the line containing the given pair of points (-7,-3) and (-2,-4)

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Question 342726: Find an equation of the line containing the given pair of points (-7,-3) and (-2,-4)
Answer by jim_thompson5910(28593) 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=-7 and y%5B1%5D=-3.
Also, is the second point . So this means that x%5B2%5D=-2 and y%5B2%5D=-4.


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


m=%28-4--3%29%2F%28-2--7%29 Plug in y%5B2%5D=-4, y%5B1%5D=-3, x%5B2%5D=-2, and x%5B1%5D=-7


m=%28-1%29%2F%28-2--7%29 Subtract -3 from -4 to get -1


m=%28-1%29%2F%285%29 Subtract -7 from -2 to get 5


So the slope of the line that goes through the points and is m=-1%2F5


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%2F5%29%28x--7%29 Plug in m=-1%2F5, x%5B1%5D=-7, and y%5B1%5D=-3


y--3=%28-1%2F5%29%28x%2B7%29 Rewrite x--7 as x%2B7


y%2B3=%28-1%2F5%29%28x%2B7%29 Rewrite y--3 as y%2B3


y%2B3=%28-1%2F5%29x%2B%28-1%2F5%29%287%29 Distribute


y%2B3=%28-1%2F5%29x-7%2F5 Multiply


y=%28-1%2F5%29x-7%2F5-3 Subtract 3 from both sides.


y=%28-1%2F5%29x-22%2F5 Combine like terms. note: If you need help with fractions, check out this solver.


y=%28-1%2F5%29x-22%2F5 Simplify


So the equation that goes through the points and is y=%28-1%2F5%29x-22%2F5


If you need more help, email me at jim_thompson5910@hotmail.com

Also, feel free to check out my tutoring website

Jim