Friday, May 18, 2007
Geometry (Class 79)
Overview
In today’s class students can complete Chapter 7: Lesson 2, if needed, and then go on to an investigation into creating patterns for circular cones.
Textbook Sections
§7.3 (Txt. p.412) Rotations
§12.3 (Txt. p.735) Surface Areas of Pyramids and Cones
Vocabulary
central angle of a cone
Key Attitudes
Mathematics is about looking for patterns.
Key Ideas
There are relationships between the coordinates of images and pre-images which are the results of reflections across lines. These relationships can be used to make predictions.
Cones can be constructed from a flat piece of paper.
The radius of the base of a cone and the slant height of the cone are key pieces of information for constructing a pattern for a cone.
The central angle of a cone can be computed using arc length.
Key Skills
Determining the location of the vertices of a figure after a reflection across the x-axis, y-axis, line y = x, or line y=-x.
Creating the image of a figure after a rotation about the origin.
Determining the angle of rotation needed to duplicate a reflection across two intersecting lines.
Identifying and measuring parts of a cone when given a pattern for the cone.
Creating a pattern for a cone given the radius and slant height.
Turn-In (#78)
No assignments due.
Handouts
Chapter 12- Making a Cone
Assignment
No Homework-- except for any class work that needs to be completed.
Disclaimer- The assignment as stated in class is the official assignment. Every effort is made to keep this posting accurate, but you should refer to what was stated in class as the final word.
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