What is the Sum of the Angles of a Triangle?

How does the Sum of Angles of a Triangle measure 180 degrees?

Can a Triangle have More than One Right Angle?

What is the Measure of each Angle of an Equilateral Triangle?

Given their Ratio; how do we Find the Measures of the Angles of a Triangle?

Sum of Angles of a Triangle – An Example

What is the Sum of Angles of a Quadrilateral?

What is the Area of a Triangle? Part 1

What is the Area of a Triangle? Part 2

What is the Relation of an Exterior Angle of a Triangle with its Interior Angles?

Exterior Angles of a Triangle – Example

What is the Triangle Inequality Theorem?

Triangle Inequality Theorem – Example

Sum of Lengths of the Sides of a Triangle is Greater than Twice the Length of the Side joining a Vertex to the Opposite Side

What is (a+b) the Whole Squared?

What is the Pythagoras’ Theorem?

How do we Derive the Pythagoras’ Theorem? Part 1

How do we Derive the Pythagoras’ Theorem? Part 2

How do we Derive the Pythagoras’ Theorem? Part 3

Which is the Longest Side in a Right Triangle?

What is the Shortest Distance to a Line from a Point not on that Line?

Pythagoras’ Theorem – An Example

Correspondence between Vertices of Two Triangles

What is Correspondence?

Correspondence between Sides and Angles

What are Congruent Figures?

When are Two Triangles Congruent?

Correspondence between Vertices of Congruent Triangles

Correspondence between Sides and Angles of Congruent Triangles

What is the RHS Congruence Condition?

How do we Prove the RHS Congruence Condition?

What is the 30-60-90 Triangle Theorem?

How do we Prove the 30-60-90 Triangle Theorem?

What is the Converse of the 30-60-90 Triangle Theorem?

How do we Prove the Converse of the 30-60-90 Triangle Theorem?

What is the Length of the Median Drawn to the Hypotenuse?

How do we Prove that the Median Drawn to the Hypotenuse is Half the Length of the Hypotenuse?

What is the Perpendicular Bisector Theorem?

How do we Prove the Perpendicular Bisector Theorem?

What is the Converse of the Perpendicular Bisector Theorem?

How do we Prove the Converse of the Perpendicular Bisector Theorem?

What is the Angle Bisector Theorem?

How do we Prove the Angle Bisector Theorem?

What is the Converse of the Angle Bisector Theorem?

How do we Prove the Converse of the Angle Bisector Theorem?

What is the Relation between Angles Opposite Unequal Sides in a Triangle?

How do we Prove that the Angle Opposite the Greater Side in a Triangle is Greater?

What is the Relation Between Sides Opposite Unequal Angles in a Triangle?

How do we Prove that the Side Opposite the Greater Angle in a Triangle is Greater?

Which is the Longest Side in a Right Triangle?

What is the Shortest Segment Theorem?

Angle Bisectors in a Triangle

Perpendicular Bisectors in a Triangle

Does the Circumcentre Always Lie Inside the Triangle?

What are Medians?

What are Medians? (In depth)

How do Medians Divide a Triangle?