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

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Question 315602: Find an equation of the line containing the points (-3, 1) and (-1, 3).
Found 3 solutions by jim_thompson5910, nyc_function, stanbon:
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=-3 and y%5B1%5D=1.
Also, is the second point . So this means that x%5B2%5D=-1 and y%5B2%5D=3.


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


m=%283-1%29%2F%28-1--3%29 Plug in y%5B2%5D=3, y%5B1%5D=1, x%5B2%5D=-1, and x%5B1%5D=-3


m=%282%29%2F%28-1--3%29 Subtract 1 from 3 to get 2


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


m=1 Reduce


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


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


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


y-1=1x%2B1%283%29 Distribute


y-1=1x%2B3 Multiply


y=1x%2B3%2B1 Add 1 to both sides.


y=1x%2B4 Combine like terms.


y=x%2B4 Simplify


So the equation that goes through the points and is y=x%2B4


Notice how the graph of y=x%2B4 goes through the points and . So this visually verifies our answer.
Graph of y=x%2B4 through the points and

Answer by nyc_function(2741) About Me  (Show Source):
You can put this solution on YOUR website!
We first find the slope.
Let m = slope
m = (3 - 1)/(-1 -(-3))
m = 2/(-1 + 3)
m = 2/2
m = 1
The slope is 1.
We now use the point-slope formula.
y - y1 = m(x - x1)
Pick one of the given points and the slope 1 to plug into the poitn-slope formula.
y - 1 = 1(x - (-3))
y - 1 = 1(x + 3)
y - 1 = x + 3
y = x + 3 + 1
y = x + 4
Done!

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find an equation of the line containing the points (-3, 1) and (-1, 3).
-----------------------
slope = (3-1)/(-1--3) = 2/2 = 1
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Form: y = mx + b
You know m = 1 and y = 1 when x = -3 ; solve for "b":
1 = 1*-3 + b
b = 4
----
Equation:
y = x + 4
=================
Cheers,
Stan H.