1/5/11 geometry bell ringer

1/5/11 Geometry Bell Ringer1. Grab today’s materials from up front.

2. Get out your homework (I’ll be around to check it); IF IT’S NOT OUT AND YOU’RE NOT

ON YOUR BELL RINGER WHEN I WALK BY YOU WILL NOT GET CREDIT.

3. Write the six congruency statements, given that

Homework: Finish 1/5 Indep. Pract.

Bell Ringer Answer

• MN QP• MP QN• NP PN

QM QPNMNP QNPMPN

M

N NP P

Q

1/5 News and Notes• Test takers – You live to fight another day…

You will take the test TOMORROW (I have a meeting after school). If this is a problem let me know.

• Perfection Award: 4th Period!

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1Perfection Competition Daily Results

1/5 Agenda

• I CAN identify SSS, SSA, SAS, ASA, SAA, AAA in a drawing and define included angles and sides.

1. Bell Ringer2. New Material – Motivation, One Example,

Vocab.3. Guided Practice4. Independent Practice

New Material – Motivation • Yesterday we did this:

And it was a pain. It felt like a lot of work to show that 2 triangles are congruent.

Today we will talk about potential shortcuts to PROVE that two triangles are congruent.

SHORTCUT!

• Rather than showing ALL 6 parts are congruent, we only have to SHOW 3.

• Now there are 6 possible combinations of 3 sides and angles that could work:

• 1. SSS• 2. SAS• 3. SSA• 4. ASA• 5. SAA• 6. AAA

Quick Examples of each

• Agile Mind 10.E.1.6• In your vocab draw examples of each of the

possible postulates.

• (SAS, SAA) KEY: When identifying the shortcuts you can skip over AT MOST 1 SIDE OR ANGLE!!! ASA,

not AAS

Examples:

• Draw the included angle between these two sides and then write the congruence shortcut that is shown:

• Draw the included side between these two angles and then write the congruence shortcut that is shown:

SAS

ASA

Guided Practice

• Determine which combois shown in each of the 5 drawings.

Independent Practice

• You now have the rest of class to work on the independent practice. Your work will be checked for progress when you walk out.