Question 369659: GIve an equation of the line given the pair of pointrs.
(1/4,-1/2) and (3/4,5)
Found 2 solutions by Alan3354, checkley77:
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! Given 2 points example.
Find the equation of the line thru the points (2,1) and (3,5)
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This is a 2 step process. First find the slope of the line thru the points.
slope, m = diffy/diffx
m = (5-1)/(3-2)
m = 4
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Now use y = mx + b with either point to find b, the y-intercept.
y = mx + b
5 = 4*3 + b
b = -7
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y = mx + b
y = 4x - 7 is the answer.
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Another approach using determinants:
|x y 1|
|2 1 1| = 0
|3 5 1|
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x(1-5) - y(2-3) + 1(10-3) = 0
-4x + y + 7 = 0
y = 4x - 7
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For further assistance, or to check your work, email me via the thank you note
or at Moral Loophole@aol.com
Answer by checkley77(12844)  (Show Source):
You can put this solution on YOUR website! (1/4,-1/2) (3/4,5)
Y=mX+b
m=(Y2-Y1)/(X2-X1)
m=(5+1/2)/(3/4-1/4)
m=4.5/.5
m=9 IS THE ANS. FOR THE SLOPE.
5=9*3/4+b
5=27/4+b
b=5-27/4
b=(20-27)/4
b=-7/4
Y=9X-7/4 ans.
 (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, 9x -7/4).
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