SOLUTION: Find an equation of the line containing the given points (1,3) and (3,4)

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Question 214767: Find an equation of the line containing the given points
(1,3) and (3,4)
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=1 and y%5B1%5D=3.
Also, is the second point . So this means that x%5B2%5D=3 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=%284-3%29%2F%283-1%29 Plug in y%5B2%5D=4, y%5B1%5D=3, x%5B2%5D=3, and x%5B1%5D=1


m=%281%29%2F%283-1%29 Subtract 3 from 4 to get 1


m=%281%29%2F%282%29 Subtract 1 from 3 to get 2


So the slope of the line that goes through the points and is m=1%2F2


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=%281%2F2%29%28x-1%29 Plug in m=1%2F2, x%5B1%5D=1, and y%5B1%5D=3


y-3=%281%2F2%29x%2B%281%2F2%29%28-1%29 Distribute


y-3=%281%2F2%29x-1%2F2 Multiply


y=%281%2F2%29x-1%2F2%2B3 Add 3 to both sides.


y=%281%2F2%29x%2B5%2F2 Combine like terms.


So the equation that goes through the points and is y=%281%2F2%29x%2B5%2F2