SOLUTION: two points on a graph. -8 4 and 6 -2. create the equaition that represents the coordinates.

Algebra ->  Linear-equations -> SOLUTION: two points on a graph. -8 4 and 6 -2. create the equaition that represents the coordinates.      Log On


   

Question 147496: two points on a graph. -8 4 and 6 -2. create the equaition that represents the coordinates.
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
The quickest and easiest way is to use determinants:
x y 1
-8 4 1 = 0
6 -2 1
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x*(4 - (-2)) - y*(-8 -6) + 1*(16-24) = 0
6x + 14y = 8
3x + 7y = 4
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Without determinants:
Find the slope m
m = (y2 - y1)/(x2 - x1)
m = (-2 -4)/(6 - (-8))
m = -6/14
m = -3/7
Then use either given point:
y - y1 = m(x - x1)
y - (-2) = (-3/7)*(x - 6)
y + 2 = (-3x +18)/7
7y + 14 = -3x + 18
3x + 7y = 4
Same answer, more work.