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Focus : How can we prove triangles congruent?. Do Now: From what you remember, list some methods of proving triangles congruent. HW: Workbook pg 67 # 2, 8. SSS. All three corresponding sides are congruent. A. B. D. C. SSS – Practice Try solving using the Side-Side-Side method.
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Focus: How can we prove triangles congruent? Do Now: From what you remember, list some methods of proving triangles congruent. HW: Workbook pg 67 # 2, 8
SSS • All three corresponding sides are congruent
A B D C SSS – PracticeTry solving using the Side-Side-Side method Given : Rectangle ABCD Prove : ▲ABC ▲ACD
ASA • Two angles and an included side are congruent.
ASA – PracticeTry solving using the Angle-Side-Angle method Given : BC bisects Angles ABC and ADC Prove : ▲ABD▲BCD A B D C
SAS • Two sides and an included angle are congruent
SAS- PracticeTry solving using the Side-Angle-Side method Given : - Angles ADB and CDB are right angles -ADDC Prove: Triangles ABD and BCD are congruent. B A C D
AAS • Two sides and a non-included angle are congruent *Note: I made a mistake on the worksheet – the diagram for AAS is actually supposed to look like this:
E D C B A F AAS- PracticeTry solving using the Angle-Angle-Side method Given- AC BD - ED ║ AF - Angle AFB Angle CED
Hy-Leg Hy-Leg • Two right triangles are congruent if their hypotenuse and one leg are congruent.
Hy-Leg - PracticeTry solving using the Hy-Leg Hy-Leg method Given: - Right triangles ABD and CDB -Angle BAD Angle BCD Prove: Triangle ABD Triangle BCD B C A D
Worksheet • Complete the worksheet in groups.
1. GIVEN: Worksheet Which method can NOT be used to prove ? a-SSS b-SAS c-AAS d-HL e-ASA
2. State whether or not each of the following triangle pairs is congruent. If so, state a reason. 3. Is ABC DBC? If so, name the postulate or theorem used. 1. State whether or not each of the following triangle pairs is congruent. If so, state a reason. 4. List the methods of proving triangles congruent. 5. Does HL imply that SSA can be used to prove triangle congruent? Explain your answer. 6. Which of the following is NOT a valid test for congruent triangles? SSA, ASA , AAS , or SAS
7. State whether or not each of the following triangle pairs is congruent. If so, state a reason. 8. State whether or not each of the following triangle pairs is congruent. If so, state a reason. 9. Given: B is the midpoint of FC. AB and FD bisect each other. AD BC Prove: angle ADF angle F 10. Is ABC DEC? If so, name the postulate or theorem used. 11. Given: BD is the median of AC. BA BCProve: ABD CBD 12. Given: ABBE, EFBE, BC DE, AD CFProve: Angle A Angle F