I have a math problem and I love stackoverflow

Question

I know it's not programming question but I thought we could all use the challenge :)

Link to diagram

Point A is the source of a laser. It is shinned at a single mirror and then reflected to another mirror finally arriving at point B ... see picture.

The goal is to find the total distance of all the lines.

I am not a student and this is not homework.

Answer 1

Same as a straight line from (-x, y) to (a, -b).

sqrt((a+x)^2 + (b+y)^2)