Download Geometry Fall 2011 Lesson 17 (S.A.S. Postulate)

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Lesson Plan #34
Date: Friday December 4th, 2015
Class: Geometry
Topic: Proving triangles congruent by
a.a.s  a.a.s.
Aim: How do we prove triangles congruent by
HW #34:
a.a.s  a.a.s. ?
Objectives:
Students will be to prove triangles congruent by
a.a.s  a.a.s.
Do Now:
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PROCEDURE:
Write the Aim and Do Now
Get students working!
Take attendance
Give Back HW
Collect HW
Go over the Do Now
Assignment #1: Complete the proof below
Statements
Reasons
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 B  E.
2)
 C  .F
2)
AC  DF .
4)  A  D.
3)
3)
5)
ABC  DEF
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4)
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Theorem: Two triangles are congruent if two angles and a side opposite one of the angles in on triangle are congruent to the
corresponding two angles and side of the other a.a.s  a.a.s.
Online Interactive Activity: Let’s see AAS in action
http://www.mathopenref.com/congruentaas.html
Does Angle Angle Angle work as a way to prove triangles congruent?
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Online Interactive Activity : Let’s go to this URL and see if Angle Angle Angle works as a way to prove triangles
congruent
http://www.mathopenref.com/congruentaaa.html
Does Angle Side Side works as a way to prove triangles congruent?
Online Interactive Activity: Let’s go to the URL and see to see if Angle Side Side works as a way to prove triangles
congruent
http://www.mathopenref.com/congruentssa.html
Assignment #2:
Assignment #3:
Assignment #4:
Given:
C is the midpoint of BE
AB || DE
Prove:
ABC  DCE
Statements
Reasons
1)
1)
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Assignment #5:
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Sample Test Questions:
1) Which of the following is not a postulate or theorem for congruence of triangles?
A) ASA
B) SAS
C) AAS
D) SSA
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If enough time:
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