Question 1043422:  use a determinent to determine whether the given points are coplaner  
(-4,1,0)(0,1,2)(4,3,-1)(0,0,1) 
 Found 2 solutions by  robertb, Alan3354: Answer by robertb(5830)      (Show Source): 
You can  put this solution on YOUR website! Let vector A = <-4,1,0>, B= <0,1,2>, C = <4,3,-1>, and D = <0,0,1>. 
We have to find the volume of the parallelipiped formed by the vectors B-A, C-A, and D-A. 
The volume is given by the triple vector product [(C-A)x(B-A)]*(D-A). 
B-A = <4,0,2>, 
C-A = <8,2,-1>, and  
D-A = <4,-1,1>.
 
===> [(C-A)x(B-A)]*(D-A) =  
 
===> the parallelipiped is actually "flat", and the points (-4,1,0), (0,1,2),(4,3,-1), and (0,0,1) are coplanar. 
 Answer by Alan3354(69443)      (Show Source): 
You can  put this solution on YOUR website! use a determinent [sic] to determine whether the given points are coplaner [sic] 
(-4,1,0)(0,1,2)(4,3,-1)(0,0,1) 
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Use the method for determining the volume of a tetrahedron. 
If the volume = 0, they're coplanar. 
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PS  it's determinant & coplanar. 
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