Voorbeeld 2
Van driehoek $ABC$ is $A(-3,0,3)$, $B(3,1,-1)$ en $C(0,1,1)$.
$
\begin{array}{l}
BC:\left( {\begin{array}{*{20}c}
x \\
y \\
z \\
\end{array}} \right) = \left( {\begin{array}{*{20}c}
3 \\
1 \\
{ - 1} \\
\end{array}} \right) + \lambda \left( {\begin{array}{*{20}c}
3 \\
0 \\
{ - 2} \\
\end{array}} \right) \\
V:3x - 2z = d \\
A\,\,op\,\,V:d = - 15 \\
V:3x - 2z = - 15 \\
3(3\lambda + 3) - 2\left( { - 1 - 2\lambda } \right) = - 15 \\
9\lambda + 9 + 2 + 4\lambda = - 15 \\
13\lambda = - 26 \\
\lambda = - 2 \\
A'( - 3,1,3) \\
d(A,BC) = \sqrt {\left( { - 3 - - 3} \right)^2 + \left( {0 - 1} \right)^2 + \left( {3 - 3} \right)^2 } = 1 \\
\end{array}
$