Question

another application of distance formula?

Answer 1

Lets use Guess and check method :).
Substitute:
D=1
C=1
B=1
A=1
1*1=1*1=1*1
1=1=1
:)

Answer 2

Crude but effective

Answer 3

unless i misunderstood your question "in point of division o a segment?"

Answer 4

Lol, questions changing on me :)