Question 1010002: Find two values of k such that the points (-3,4), (0,k), and (k,10) are collinear.
Found 2 solutions by stanbon, MathLover1: Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Find two values of k such that the points (-3,4), (0,k), and (k,10) are collinear.
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Look at the slopes::
1st point to 3rd point::
(k-4)/(0+3) = (10-4)/(k+3)
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Cross multiply::
k^2 - k - 12 = 3*6
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k^2 - k - 30 = 0
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(k-6)(k+5) = 0
k = 6 or k = -5
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Cheers,
Stan H.
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Answer by MathLover1(20849) (Show Source):
You can put this solution on YOUR website! Find two values of k such that the points ( , ), ( , ), and ( , ) are collinear.
the points are collinear if they lie on same line
use the slope of a line to find
for the points ( , ), ( , ),
.............eq.1
for ( , ), and ( , )

............eq.2
from eq.1 and eq.2 we have
............cross multiply


...........factor completely



solutions:

so, the points ( , ), ( , ), and ( , ) are collinear
and the points ( , ), ( , ), and ( , ) are collinear
now find slope
.............eq.1 if 

.............eq.1 if 


so, there are possible lines and they are
and
we need y-intercepts
use one point : ( , )

and
use one point : ( , )
so, the line contains points the points ( , ), ( , ), and ( , )
and the line contains points the points ( , ), ( , ), and ( , )
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