For each figure state the number of sides of symmetry and all the angles of rotational symmetry.
I believe "sides of symmetry" refers to lines of symmetry.
Thank you for your help.
1 Answer | Add Yours
Lines of symmetry indicate reflection symmetry.
The isosceles triangle only has 1 line of symmetry. The line of symmetry is from the 3rd angle through the base that contains the congruent base angles. There are no other lines in which the image could be reflected.
For rotational symmetry to exist for the isosceles triangle that would only be 360 degrees, if rotating about the center.
For the parallelogram, it has no lines of symmetry as no adjacent sides or angles are equal. In order to have reflection symmetry, it needs to be a "mirror" image across the line of reflection. This has none.
For angles of rotation, this image has 180 degrees and 360 degrees rotation about the center.
Join to answer this question
Join a community of thousands of dedicated teachers and students.Join eNotes