Question

Describe objects that have each of the following types of symmetry. Line, Point, Plane, 90° rotational

Answer 1

Point symettry is oft called rotational symettry. Things can be rotated x degrees, and the image is the same.
Examples:
http://www.mathsisfun.com/geometry/images/king-of-hearts.jpg
THe letters X, I, have point symettry, they can be rotated 180 degrees. They also have plane symettry, later.
here is my favorite point symettry:
http://upload.wikimedia.org/wikipedia/commons/thumb/a/a9/Haeckel_Actiniae.jpg/420px-Haeckel_Actiniae.jpg
Line symmetry:
symmetry about a line http://images.google.com/images?hl=en&client=firefox-a&hs=Xhh&rls=org.mozilla:en-US:official&resnum=0&q=line+symmetry&um=1&ie=UTF-8&sa=N&tab=wi
plane symettry: same as line, but three dimensional.
http://www.johnchiappone.com/images/humanities/Brooklyn-Bridge.jpg
90 rotational: a variation of point.
http://t2.gstatic.com/images?q=tbn:CLBaialB2ikgUM:http://euler.slu.edu/escher/upload/thumb/5/51/Baby-starfish.jpg/250px-Baby-starfish.jpg

Now usually, these are added together,in clever methods. Here is one clever art-math student
http://vectortuts.s3.cdn.plus.org/articles/article_40_clever_ambigrams/infinitycircler.jpg