Question 490784: Write the equation of the line AB that passes through the following points: A(-2,4) B(5,6)
and A(-3,-4) B(2,8)
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! Write the equation of the line AB that passes through the following points:
A(-2,4) B(5,6)
Find the slope, m = diffy/diffx
m = (4-6)/(-2-5) = -2/-7
m = 2/7
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Use y = mx + b and either point to find b
6 = (2/7)*5 + b
b = 6 - 10/7
b = 32/7
y = mx + b
y = (2/7)x + 32/7 Slope-intercept form
2x - 7y = -32 Standard form
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and A(-3,-4) B(2,8)
Do it like the 1st one, or
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use determinants
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|+x +y +1|
|-3 -4 +1| = 0
|+2 +8 +1|
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x(-4-8) -y(-3-2) + (-24+8) = 0
-12x + 5y = 16
12x - 5y = -16
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