Chapter 10 Polygons! lvillage.education.vic.gov.au/.../polygons.JPG

3/25- Notes: Chapter 10- sections 6&7 Symmetry and Tessellations Goals: By the end of today, you should be able to Determine whether a figure has line and/or rotational symmetry. 2. Determine whether a tessellation is regular, semi-regular or neither. 3. Construct different types of tessellations using dot paper.

Line Symmetry A figure has line symmetry if you can draw a _______ through the middle of it and each half is a ____________ of the other half pr- 2.gif&imgrefurl= h=300&w=300&sz=3&hl=en&start=13&tbnid=BKkj4XtxIKV9nM:&tbnh=116&tbnw=116&prev=/images%3Fq%3DLine%2BSymmetry%26gbv%3D2%26hl%3Den%26sa% 3DG Goal #1

Line Symmetry How do I tell if a figure has line symmetry? How do I tell how many lines of symmetry a figure has? Goal #1

Rotational Symmetry If a figure can be ________ less than ____ so that it looks exactly the same as the ________, then it has rotational symmetry. gwydir.demon.co.uk/jo/symmetry/exsym8.gif Goal #1

Rotational Symmetry How do I tell if a figure has rotational symmetry? How do I tell what the degrees of rotation would be? 90° 180° Goal #1

Pause to practice Goal #1 Line Symmetry 1.Does a figure have it? 2.If so, how many lines of symmetry does it have? Rotational Symmetry 1.Does a figure have it? 2.If so, what are the degrees of each turn?

Tessellations Tessellation- a repeating pattern formed by polygons that have no overlapping or gapping. Let’s check out some more of this famous math geek/artist’s work blauereiter.motime.com/archive/

Tessellations Regular- a tessellation formed by _________ regular polygon. More regular tesselations Semi-regular- a tessellation formed by ______ or more regular polygons. More semi-regular tesselations If a tessellation has any shapes that are not regular polygons, then it is neither. rms.hamp.k12.wv.us/.../TessellationsOnline.html Goal #2

Pause to practice Goal #2 Tessellations 1.Is there any overlaps or gaps? 2.If not, what kinds of shapes make up the tesselation?