Wednesday, March 11, 2009
Geometry (Class 59)
Announcements
Test Friday- Using Congruent Triangles
Lesson Title
Similar Triangles (2)
Overview
The opener today reviews solving quadratic equations by factoring as well as gives students another opportunity to use proving triangles congruent to prove another fact. The lesson will continue with working with Similar triangles.
Textbook Sections
§8.4 (Txt. p. 480) Similar Triangles
Vocabulary
construction
straight edge
arc
radius
center
diameter
adjacent
opposite
included
non-included
SSS
ASA
SAS
AAS
HL
Key Attitudes
Math is about building up understanding one idea at a time.
Key Ideas
Triangles can be constructed out of various combinations of angles and sides.
Only some combinations of angles and sides guarantee that all triangle created with this combination will be congruent-- the same size and the same shape. Other combinations only guarantee triangles which are the same shape, and some combinations guarantee nothing at all!
Triangles which are the same shape always have some key attributes.
Key Skills
I can identify key angle and side combinations which force triangles to be congruent.
I can identify and sequence the reasons which establish triangle congruence.
I can use congruent triangles to prove other facts.
I can use a straight edge and compass to construct geometric shapes.
Turn-In (#58)
Txt. p.258 #16-18, 24-27, 39-42
Chapter 4- Lesson 4
CST Review
Handouts
No Handouts Posted
Assignment
Txt. p.250 #1, 2 (Hint: Do you see isosceles triangles?)
Txt. p.258 #28-30, 43-48
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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