SOLUTION: i whant to know how to find the linear equation that passes through (5,-7) and (-1,3)

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Question 339956: i whant to know how to find the linear equation that passes through (5,-7) and (-1,3)
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=%283--7%29%2F%28-1-5%29 Plug in y%5B2%5D=3, y%5B1%5D=-7, x%5B2%5D=-1, and x%5B1%5D=5


m=%2810%29%2F%28-1-5%29 Subtract -7 from 3 to get 10


m=%2810%29%2F%28-6%29 Subtract 5 from -1 to get -6


m=-5%2F3 Reduce


So the slope of the line that goes through the points and is m=-5%2F3


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--7=%28-5%2F3%29%28x-5%29 Plug in m=-5%2F3, x%5B1%5D=5, and y%5B1%5D=-7


y%2B7=%28-5%2F3%29%28x-5%29 Rewrite y--7 as y%2B7


y%2B7=%28-5%2F3%29x%2B%28-5%2F3%29%28-5%29 Distribute


y%2B7=%28-5%2F3%29x%2B25%2F3 Multiply


y=%28-5%2F3%29x%2B25%2F3-7 Subtract 7 from both sides.


y=%28-5%2F3%29x%2B4%2F3 Combine like terms. note: If you need help with fractions, check out this solver.


y=%28-5%2F3%29x%2B4%2F3 Simplify


So the equation that goes through the points and is y=%28-5%2F3%29x%2B4%2F3

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

Also, feel free to check out my tutoring website

Jim