This math video provides an introduction into triangles. It explains the classification of triangles based on their angle measure and the number of congruent sides. Examples include equilateral triangles, scalene triangles, isosceles, right, acute, and obtuse triangles. This video also contains practice problems on solving the angle measure of triangles.

Lines, Rays, Line Segments, & Angles:    • Lines, Rays, Line Segments, Points, A...  
Acute, Obtuse, Right, & Straight Angles:    • Acute Obtuse Right & Straight Angles ...  
Decimal Degrees to DMS Formula:    • Decimal Degrees to DMS Formula   Con...  
Clock to Angle Problems:    • Clock Aptitude Reasoning Tricks & Pro...  
Angle Bisector Theorem Midpoints:    • Angle Bisector Theorem  Midpoints & ...  
Converse, Inverse, & Contrapositive:    • Converse, Inverse, & Contrapositive ...  
Geometry Probability Length & Area:    • Probability With Geometry  Length, A...  
Perpendicular Lines, Rays, & Segments:    • Perpendicular Lines, Slope, Rays, and...  
Complementary & Supplementary Angles:    • Complementary Angles and Supplementar...  
Addition & Subtraction Equality Property:    • Addition and Subtraction Property of ...  
Multiplication & Division Property Equality:    • Multiplication and Division Property ...  
Transitive Property of Congruence:    • Transitive Property of Congruence & S...  
Triangles Basic Introduction:    • Triangles  
Alternate Interior & Exterior Angles:    • Parallel and Perpendicular Lines, Tra...  
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2 Column Proofs of Congruent Segments:    • Two Column Proofs of Congruent Segmen...  
2 Column Proofs of Angles:    • Geometry, Two Column Proofs of Angles...  
Triangle Congruence SSS, SAS, ASA:    • Triangle Congruence Theorems, Two Col...  
CPCTC 2 Column Proofs With Triangles:    • CPCTC Geometry Proofs Made Easy, Tria...  
Median of a Triangle Formula:    • Median of a Triangle Formula, Example...  
Altitude of a Triangle Orthocenter:    • Altitude of a Triangle  Finding The ...  
Triangles, Medians, & Altitudes Proofs:    • Two Column Proofs  Triangles, Median...  
2 Column Proofs Isosceles Triangles:    • Geometry Proofs  Isosceles Triangles...  
Angle Side Theorem 2 Column Proofs:    • Angle Side / BaseAngle Theorem  Two...  
Hypotenuse Leg Theorem HL Postulate:    • Hypotenuse Leg Theorem  HL Postulate...  
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Detour Proofs Double Triangle Congruence:    • Detour Proofs  Double Triangle Congr...  
The Midpoint Formula:    • Midpoint Formula  
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  ...  
Indirect Proofs Example Problems:    • Indirect Proofs, Practice Problems, T...  
Proving Parallel Lines With Proofs:    • Proving Parallel Lines With Two Colum...  
The Exterior Angle Theorem:    • Exterior Angle Theorem For Triangles,...  
Exterior Angle Inequality Theorem:    • Exterior Angle Inequality Theorem Wit...  
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Polygons:    • Polygons  
Quadrilaterals:    • Quadrilaterals  Geometry  
Parallelograms:    • Parallelograms  Geometry  
Rectangles Special Quadrilaterals:    • Rectangles  Properties of Parallelog...  
Isosceles Trapezoids:    • Isosceles Trapezoids  
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Geometry Review Study Guide:    • Geometry Introduction  Basic Overvie...  
Geometry Final Exam Review Questions:    • Geometry Final Exam Review  Study Guide