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| Question 64875:   write an equation in slope intercept form for the line passing through each pair of points
 1. (-1,3) and (2,-5)
 
 Answer by Edwin McCravy(20064)
      (Show Source): 
You can put this solution on YOUR website! Write an equation in slope intercept form 
for the line passing through the pair of points
 (-1,3) and (2,-5)
First use the equation for the slope:
     y2 - y1
m = —————————
     x2 - x1
where (x1, y1) = (-1, 3) and (x2, y2) = (2, -5)
      (-5) - (3)      -5 - 3     -8
m = —————————————— = ———————— = ———— = -8/3
      (2) - (-1)       2 + 1      3 
Now substitute in the point slope formula:
y - y1 = m(x - x1)
y - 3 = (-8/3)( x - (-1) )
y - 3 = (-8/3)(x + 1)
y - 3 = (-8/3)x - 8/3
Multiply both side by LCD = 3
  3y - 9 = -8x - 8
 8x + 3y = 1
That's the answer in standard form. If you
need it to be in slope-intercept form, solve
it for y:
     3y = -8x + 1
      y = (-8/3)x + 1/3
Edwin
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