Question

If A(x1, y1), B(x2, y2), C(x3, y3), and D(x4, y4) form two line segments, AB and CD , which condition needs to be met to prove AB is perpendicular to CD ?

Answer 1

AB=?
CD=?

Answer 2

A(x1, y1), B(x2, y2), C(x3, y3), and D(x4, y4)

Answer 3

nope, I ask AB , not A, B

Answer 4

doesn't tell you

Answer 5

hahaha... keep it in secret?? ok, so, I don't know what AB and CD are. How can I help you to solve it?

Answer 6

if the problem doesn't tell you, you have to find them out.

Answer 7

i dont know how to solve this problem

Answer 8

Ok,
AB = (x2-x1, y2-y1)
CD=? your turn

Answer 9

well then how

Answer 10

answer me first, what is CD