SOLUTION: Find an equation for this line (-4,1) and (7,-5)

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Question 177158: Find an equation for this line (-4,1) and (7,-5)
Found 2 solutions by jim_thompson5910, 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


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


m=%28-5-1%29%2F%287--4%29 Plug in y%5B2%5D=-5, y%5B1%5D=1, x%5B2%5D=7, and x%5B1%5D=-4


m=%28-6%29%2F%287--4%29 Subtract 1 from -5 to get -6


m=%28-6%29%2F%2811%29 Subtract -4 from 7 to get 11


So the slope of the line that goes through the points and is m=-6%2F11


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=%28-6%2F11%29%28x--4%29 Plug in m=-6%2F11, x%5B1%5D=-4, and y%5B1%5D=1


y-1=%28-6%2F11%29%28x%2B4%29 Rewrite x--4 as x%2B4


y-1=%28-6%2F11%29x%2B%28-6%2F11%29%284%29 Distribute


y-1=%28-6%2F11%29x-24%2F11 Multiply


y=%28-6%2F11%29x-24%2F11%2B1 Add 1 to both sides.


y=%28-6%2F11%29x-13%2F11 Combine like terms. note: If you need help with fractions, check out this solver.


So the equation that goes through the points and is y=%28-6%2F11%29x-13%2F11

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find an equation for this line (-4,1) and (7,-5)
-------------------------------------------------
slope = (-5-1)/(7--4) = -6/11
intercept: 1 = (-6/11)(-4) + b
b = 1 -(24/11)
b = -13/11
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y = (-6/11)x - (13/11)
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Cheers,
Stan H.