titik A(2,0,3), B(-3,1,n+2) dan C(m,-2,-1) segaris, nilai m-4n adalah...

AB=B-C
=(-3,1,n+1)-(2,0,3)
=(-5,1,n-2)
BC=C-B
=(m,-2,-1)-(-3,1,n+1)
=(m+3,-3,n)

AB=kxBC
(-5,1,n-2)=kx(m+3,-3,n)

=>-5=k.m+3
1=k.-3 -->k=-1/3
n-2=k.n
=>-5= k.m+3
-5=-1/3.m+3
-5.-3=m+3
m=15/3=5
=>n-2=k.n
n-2=-1/3.n
-2.-3=n+n
-6=2n
n=-6/2=-3

Maka:
m-4n
5-4.-3
5+12=17