D.Edmundson Kirkland Math II
If Leonardo Da Vinci could ask me to practice on a particular thing when writing sentences in a reflection, I believe that he would ask me to practice on writing in a straight line and to practice on making my words and letters much neater. To make sure that my A's actually looked like A's and not just O's with a line. Mirror writing may have seemed natural to him because of the unique fact of him being born left-handed.
In this picture, triangle ABC is reflected over line m. The reflection of triangle ABC equals triangle A'B'C'.
This picture shows a triangle being reflected over a line of reflection.