SOLUTION: What is the equation of the line that contains (7, -9) and (7, 3)?

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Question 199370: What is the equation of the line that contains (7, -9) and (7, 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


Note: is the first point and is the second point .


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


m=%283--9%29%2F%287-7%29 Plug in y%5B2%5D=3, y%5B1%5D=-9, x%5B2%5D=7, and x%5B1%5D=7


m=%2812%29%2F%287-7%29 Subtract -9 from 3 to get 12


m=%2812%29%2F%280%29 Subtract 7 from 7 to get 0


Remember, you cannot divide by zero. So this means that the slope is undefined.


Since the slope is undefined, this means that the equation of the line through the points and is x=7 (which is a vertical line).