Basic Concepts of Geometry

Lesson 1: Points, Lines, and Planes
Lesson 2: How to Name Angles
Lesson 3: How to Measure Angles
Lesson 4: Definition and Names of Polygons
Lesson 5: Parts of a Triangle
Lesson 6: Types of Triangles According to Sides and Angles
Lesson 7: Lines, Rays, and Segments
Lesson 8: Meaning of Collinear and Coplanar
Lesson 9: Congruence of Segments
Lesson 10: Congruence of Angles
Lesson 11: Complementary and Supplementary Angles
Lesson 12: Adjacent Angles and Linear Pairs
Lesson 13: Vertical Angles – Definition and Proof
Lesson 14: Parallel, Perpendicular, and Skew Lines


Lesson 1: Basic Terminologies about Quadrilaterals
Lesson 2: Sum of the Interior Angles of Quadrilateral
Lesson 3: Definition of Parallelogram and Its Properties
Lesson 4: Proof that Opposite Sides of a Parallelogram are Congruent
Lesson 5: Proof that Opposite Angles of Parallelogram Are Congruent
Lesson 6: Proof that Diagonals of Parallelograms Divide it to Congruent Triangles
Lesson 7: Proof that Diagonals of a Parallelogram Bisect Each Other
Lesson 8: Proof that if Opposite Sides of a Quadrilateral are Congruent It is a Parallelogram
Lesson 9: Proof that if Opposite Angles of a Quadrilateral are Congruent It is a Parallelogram
Lesson 10:  If the diagonals of a quadrilateral bisect each other, it is a parallelogram
Lesson 11: If one pair of sides of a quadrilateral are both congruent and parallel, it is a parallelogram
Lesson 12:  Definitions of Rectangles, Rhombuses, and Squares
Lesson 13: Diagonals of a Rectangle are Congruent
Lesson 14:  Diagonals of a Rhombus are Perpendicular
Lesson 15:  Definition and Parts of a Trapezoid
Lesson 16: Base Angles of Isosceles Trapezoid are Congruent

Triangle Congruence

Lesson 1: Introduction to Triangle Congruence
Lesson 2: Minimum Conditions for Triangle Congruence
Lesson 3: The SSS Congruence
Lesson 4: The ASA Congruence
Lesson 5: The SAS Congruence
Lesson 6: Sample Proof Using SSS Congruence
Lesson 7: Sample Proof Using ASA Congruence
Lesson 8:  Sample Proof Using SAS Congruence
Lesson 9: Leg Leg Congruence (LL Congruence)
Lesson 10:  Leg Angle Congruence (LA Congruence)
Lesson 11: AAS Congruence and its Proof
Lesson 12: Hypotenuse Angle Congruence