This geometry video tutorial provides a basic introduction into the exterior angle theorem for triangles. It explains how to use it solve for x and y. It describes the difference between interior angles and exterior angles as well as the remote interior angles. It contains plenty of examples and practice problems.

Triangle Congruence - SSS, SAS, ASA:
   • Triangle Congruence Theorems, Two Col...  

CPCTC - 2 Column Proofs With Triangles:
   • CPCTC Geometry Proofs Made Easy, Tria...  

Hypotenuse Leg Theorem - HL Postulate:
   • Hypotenuse Leg Theorem - HL Postulate...  

Detour Proofs - Double Triangle Congruence:
   • Detour Proofs - Double Triangle Congr...  

The Midpoint Formula:
   • Midpoint Formula  

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Missing Diagrams - 2 Column Proofs:
   • Missing Diagrams With Two Column Proofs  

Right Angle Theorem - SSS & SAS:
   • Right Angle Theorem - SSS & AAS - Two...  

Perpendicular Bisector Theorem:
   • Perpendicular Bisector of a Line Segm...  

Altitude, Median, Midpoint & P. Bisector:
   • Altitudes, Medians, Midpoints, Angle ...  

Parallel & Perpendicular Lines - Slope:
   • Finding The Slope Given Two Points - ...  

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Indirect Proofs - Example Problems:
   • Indirect Proofs, Practice Problems, T...  

Proving Parallel Lines With Proofs:
   • Proving Parallel Lines With Two Colum...  

Exterior Angle Inequality Theorem:
   • Exterior Angle Inequality Theorem Wit...  

Polygons:
   • Polygons  

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