See if the following helps. The dotted lines are construction lines. Three are needed to create triangle image. Then draw dotted line from LL to P. Then draw line from L to K and from K to P.
Further to my reply #1, I should have said that the construction lines from the three vertices of the triangle should be perpendicular to the mirror and the same length behind the mirror as in front.
See if the following helps. The dotted lines are construction lines. Three are needed to create triangle image. Then draw dotted line from LL to P. Then draw line from L to K and from K to P.
