1. The problem statement, all variables and given/known data The book ("Real World Physics") says A virtual image in a plane mirror is on the perpendicular from the object to the mirror 2. Relevant equations I know that the normal line is perpendicular to the surface of the mirror And I know that the angle of the incidence and reflection are the same degrees as each other with respect to the normal.. But I don't get what they mean by the sentence above https://en.wikipedia.org/wiki/Plane_mirror#/media/File:Plane_mirror.png [wikicommons image] 3. The attempt at a solution I don't see any right angles in the image above and I can't visualise any when I look in the mirror. I doubled check to make sure that perpendicular always means at a right angle.. and it does... Can someone explain what is meant by this? Thank you!