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CPCTC Geometry Proofs Made Easy, Triangle Congruence – SSS, SAS, ASA, & AAS, Two Colmn Proofs

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This video tutorial provides a basic introduction into CPCTC geometry proofs. CPCTC stands for “corresponding parts of congruent triangles are congruent” It’s the step that comes right after proving the congruence of two triangles. Some triangle congruence theorems you need to know are the SSS, SAS, ASA, and AAS postulates – examples of which are all covered in this lecture. This video contains plenty of practice problems on two column proofs. Topics include midpoints, parallel lines, perpendicular lines, right angles, reflexive property, addition and subtraction property of equality, definition of congruent segments, segment addition, congruent angles, vertical angles, circles & radii, base angle theorem, angle bisectors, segment bisectors, overlapping triangles, and alternate interior angles.

2 Column Proofs of Congruent Segments:

2 Column Proofs of Angles:

Triangle Congruence – SSS, SAS, ASA:

CPCTC – 2 Column Proofs With Triangles:

Median of a Triangle Formula:

Altitude of a Triangle – Orthocenter:

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Triangles, Medians, & Altitudes – Proofs:

2 Column Proofs – Isosceles Triangles:

Angle Side Theorem – 2 Column Proofs:

Hypotenuse Leg Theorem – HL Postulate:

Detour Proofs – Double Triangle Congruence:

Missing Diagrams – 2 Column Proofs:

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