40  x 4x – 20  Solve. Warm up 1. 2y + 28  3y – 14° 

Questions over HW? Did you have hw?

Congruent Triangles

Congruent triangles have 3 congruent sides and 3 congruent angles. The parts of congruent triangles that “match” are called corresponding parts.

In a congruence statement ORDER MATTERS!!!! Everything matches up.

Corresponding Parts of Congruent Triangles are Congruent

Complete each congruence statement. C A E D B F If  ABC   DEF, then BC  ___ EF

Complete each congruence statement. C A E D B F If  ABC   DEF, then  A  ___ DD

Complete each congruence statement. C A E D B F If  ABC   DEF, then  C  ___ FF

Fill in the blanks If  CAT   DOG, then AC  ___ OD

Fill in the blanks  BAT   MON  T  ___ _____   ONM _____  MO NM  ____ NN  ATB BA TB

Fill in the blanks  BCA   ____  ____   GFE EGF CAB

Complete the congruence statement.  _____   JKN MKL

Complete the congruence statement.  _____   CBD ABD

5 ways to Prove Triangles Congruent

Side-Side-Side (SSS) Congruence Postulate All Three sides in one triangle are congruent to all three sides in the other triangle

Side-Angle-Side (SAS) Congruence Postulate Two sides and the INCLUDED angle (the angle is in between the 2 marked sides)

Angle-Angle-Side (AAS) Congruence Postulate Two Angles and One Side that is NOT included

Angle-Side-Angle (ASA) Congruence Postulate Two angles and the INCLUDED side (the side is in between the 2 marked angles)

There is one more way to prove triangles congruent, but it’s only for RIGHT TRIANGLES…Hypotenuse Leg

Your Only Ways To Prove Triangles Are Congruent NO BAD WORDS

3 markings YOU can add if they aren’t marked already

Share a side Reason: Reflexive Property Vertical Angles Reason: Vertical Angles are congruent

Alternate Interior Angles Reason: Alt. Int angles are congruent

Homework WS #1 – 12