SOLUTION: find the equation of th linee going through (7,9) & (6,2)

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Question 639009: find the equation of th linee going through (7,9) & (6,2)
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


Note: is the first point . So this means that x%5B1%5D=7 and y%5B1%5D=9.
Also, is the second point . So this means that x%5B2%5D=6 and y%5B2%5D=2.


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


m=%282-9%29%2F%286-7%29 Plug in y%5B2%5D=2, y%5B1%5D=9, x%5B2%5D=6, and x%5B1%5D=7


m=%28-7%29%2F%286-7%29 Subtract 9 from 2 to get -7


m=%28-7%29%2F%28-1%29 Subtract 7 from 6 to get -1


m=7 Reduce


So the slope of the line that goes through the points and is m=7


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-9=7%28x-7%29 Plug in m=7, x%5B1%5D=7, and y%5B1%5D=9


y-9=7x%2B7%28-7%29 Distribute


y-9=7x-49 Multiply


y=7x-49%2B9 Add 9 to both sides.


y=7x-40 Combine like terms.


So the equation that goes through the points and is y=7x-40