Isosceles Triangle Theorem (Base Angles Theorem)

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Presentation transcript:

Isosceles Triangle Theorem (Base Angles Theorem) If two sides of a triangle are congruent (isosceles triangle), then the angles opposite them are congruent A B C

J K L Given: Prove M Statements Reasons 1. M as the midpoint of 1. Definition of a median 2. 2. Definition of a midpoint 3. 3. Given 4. 4. Reflexive Property 5. 5. 6. 6.

Converse of the Isosceles Triangle Theorem (Converse of the Base Angles Theorem) If two angles of a triangle are congruent, then the sides opposite them are congruent B C A

J K L Given: Prove M Statements Reasons 1. 1. Definition of an angle bisector 2. 2. Reflexive Post 3. 3. Given 4. 4. 5. 5.