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Geometry

This fully accredited, Common Core-aligned Geometry course provides a comprehensive treatment of high-school geometry. Students will deep-dive into geometric transformations, congruence, similarity, mathematical proof, circles, radians, coordinate geometry, elementary trigonometry, solid geometry, probability, and combinatorics. This course lays the foundations for progression onto Algebra II, where more advanced geometrical and trigonometric concepts are encountered.

Overview

Outcomes

Content

The concept of a rigorous mathematical proof is introduced. Students begin by exploring proof fundamentals, such as postulates, definitions, theorems, and the properties of congruence. Once mastered, they will use these ideas to prove important geometric theorems. Opportunities to demonstrate and develop their proof-writing skills are ongoing throughout this course.

Students will explore geometric transformations in the plane. They will construct functions that represent specific mappings and apply these functions to manipulate various geometric objects.

The course introduces the concept of rigid motions as transformations that preserve both distance and angle. Students will learn to identify whether a given transformation qualifies as a rigid motion and describe the concept of congruence in terms of rigid motions. Additionally, students will master the congruence criteria for triangles and use them to prove mathematical statements.

Progressing from the concept of congruence, students explore the notion of similarity. They will learn to describe similarity through similarity transformations and apply similarity concepts to solve problems involving similar polygons. Students will proficiently use the AA, SSS, and SAS similarity criteria and construct formal proofs about similar triangles.

Students will undertake a deep exploration of circles. They begin by studying circle fundamentals such as circumference, area, and circular sectors. Various circle theorems are introduced, including the inscribed angle theorem, Thales' theorem, and the tangent-chord theorem. Students will solve problems involving secant and tangent lines to circles, explore the concept of radian measure, and construct formal proofs demonstrating that any two circles are similar.

Much of this course is dedicated to extending students' knowledge to problems within the coordinate plane. They will derive equations of parallel and perpendicular lines, calculate distances and midpoints in the plane, partition line segments, and apply their knowledge to compute areas and perimeters of polygons. Students will transfer their knowledge of circle theorems to coordinate plane problems.

A key objective of this course is to deepen students' understanding of triangles. Students will become proficient in applying the Pythagorean theorem, understand its role in deducing properties of special right triangles, and use this knowledge to solve more complex problems. Students will have the opportunity to prove multiple triangle theorems. Moreover, they will encounter trigonometric ratios, solve problems requiring computing angles and side lengths of right triangles, and apply these skills to more complex scenarios.

Students will expand their geometric knowledge beyond the plane, exploring both polyhedra and non-polyhedra. They will learn to calculate volumes and surface areas of multiple shapes and solve related problems. Concepts such as Euler's formula for polyhedra, the Platonic solids, and volumes of revolution will also be introduced.

Finally, students develop their understanding of probability and combinatorics. They will explore events, Venn diagrams, unions and intersections of events, the addition law, conditional probability, tree diagrams, permutations, and combinations. Throughout this unit, students will practice applying these concepts to model real-world problems.

Upon successful completion of this course, students will have mastered the following:

Congruence, Similarity, & Proof

Circles & Radian Measure

Geometry in the Coordinate Plane

Triangles, Quadrilaterals, & Trigonometry

Solid Geometry

Probability & Combinatorics

1.
Proof, Congruence, & Similarity
40 topics
1.1. Proof
1.1.1. Introduction to Geometric Proofs
1.1.2. Proving Alternate Angle Theorems
1.1.3. Proving Consecutive Angle Theorems
1.1.4. Further Proving Consecutive Angle Theorems
1.1.5. Proving Perpendicular Line Theorems
1.1.6. Further Proving Perpendicular Line Theorems
1.2. Transformations
1.2.1. Translations of Geometric Figures
1.2.2. Rotations of Geometric Figures
1.2.3. Rotating Objects in the Coordinate Plane Using Functions
1.2.4. Reflections of Geometric Figures in the Cartesian Plane
1.2.5. Reflections of Figures Across Arbitrary Lines
1.2.6. Dilations of Geometric Figures
1.2.7. Dilations of Figures in the Coordinate Plane
1.2.8. Stretches of Geometric Figures
1.2.9. Combining Stretches of Geometric Figures
1.2.10. Combining Geometric Transformations
1.2.11. Reflective Symmetry
1.2.12. Rotational Symmetry
1.3. Congruence
1.3.1. The ASA Congruence Criterion
1.3.2. The AAS Congruence Criterion
1.3.3. The SAS Congruence Criterion
1.3.4. The SSS Congruence Criterion
1.3.5. The HL Congruence Criterion
1.3.6. Combining Congruence Criteria for Triangles
1.3.7. Rigid Motions and Congruence
1.3.8. Properties of Congruence
1.3.9. Proving Congruence Statements
1.4. Similarity
1.4.1. Similarity and Similar Polygons
1.4.2. Side Lengths and Angle Measures of Similar Polygons
1.4.3. Areas of Similar Polygons
1.4.4. Working With Areas of Similar Polygons
1.4.5. Similarity Transformations
1.4.6. The AA Similarity Criterion
1.4.7. The SSS Similarity Criterion
1.4.8. The SAS Similarity Criterion
1.4.9. Combining Similarity Criteria for Triangles
1.4.10. Proving Similarity Statements
1.4.11. The Midpoint Theorem
1.4.12. Proving the Midpoint Theorem
1.4.13. The Triangle Proportionality Theorem
2.
Circles & Radian Measure
27 topics
2.5. Circles Essentials
2.5.1. Circles
2.5.2. Arcs, Segments, and Sectors of Circles
2.5.3. The Circumference of a Circle
2.5.4. Areas of Circles
2.5.5. Central Angles and Arcs
2.5.6. Calculating Arc Lengths of Circular Sectors
2.5.7. Calculating Areas of Circular Sectors
2.5.8. Further Calculating Areas of Sectors
2.5.9. Problem Solving With Circles
2.5.10. Inscribed Circles and Squares
2.6. Circle Theorems
2.6.1. Inscribed Angles
2.6.2. Problem-Solving With Inscribed Angles
2.6.3. Thales' Theorem
2.6.4. Angles in Inscribed Right Triangles
2.6.5. Further Angles in Inscribed Right Triangles
2.6.6. Inscribed Quadrilaterals
2.6.7. Tangent Lines to Circles
2.6.8. Tangent-Tangent Lines to Circles
2.6.9. Secant-Secant Angles to Circles
2.6.10. Secant-Tangent Angles to Circles
2.6.11. The Tangent-Chord Theorem
2.6.12. Circle Similarity
2.6.13. Proving Circle Similarity
2.7. Radians
2.7.1. Introduction to Radians
2.7.2. Calculating Arc Length Using Radians
2.7.3. Calculating Areas of Sectors Using Radians
2.7.4. Trigonometric Ratios With Radians
3.
Geometry in the Coordinate Plane
21 topics
3.8. Coordinate Geometry
3.8.1. Parallel Lines in the Coordinate Plane
3.8.2. Finding the Equation of a Parallel Line
3.8.3. Perpendicular Lines in the Coordinate Plane
3.8.4. Finding Equations of Perpendicular Lines
3.8.5. Midpoints in the Coordinate Plane
3.8.6. Partitioning Line Segments
3.8.7. The Distance Formula
3.8.8. The Shortest Distance Between a Point and a Line
3.8.9. Calculating Perimeters in the Plane
3.8.10. Calculating Areas of Rectangles in the Plane
3.8.11. Calculating Areas of Triangles and Quadrilaterals in the Plane
3.9. Circles in the Coordinate Plane
3.9.1. Circles in the Coordinate Plane
3.9.2. Equations of Circles Centered at the Origin
3.9.3. Equations of Circles
3.9.4. Determining Circle Properties by Completing the Square
3.9.5. Calculating Circle Intercepts
3.9.6. Intersections of Circles with Lines
3.9.7. Equations of Tangent Lines to Circles
3.9.8. Perpendicular Bisectors of Diameters
3.9.9. Perpendicular Bisectors of Chords
3.9.10. Thales' Theorem in the Coordinate Plane
4.
Triangles, Quadrilaterals, & Trigonometry
27 topics
4.10. Triangles
4.10.1. The Exterior Angle Theorem
4.10.2. The Pythagorean Theorem
4.10.3. The 45-45-90 Triangle
4.10.4. The 30-60-90 Triangle
4.10.5. The Area of a 45-45-90 Triangle
4.10.6. The Area of a 30-60-90 Triangle
4.10.7. The Area of an Equilateral Triangle
4.10.8. Proving Triangle Theorems
4.10.9. Proofs Involving Isosceles Triangles
4.10.10. Medians and Centroids of Triangles
4.10.11. Proofs Involving Medians and Centroids
4.11. Quadrilaterals
4.11.1. Diagonals of Squares
4.11.2. Properties of Parallelograms
4.11.3. Proving Properties of Parallelograms
4.11.4. Proving Criteria for Parallelograms and Rectangles
4.12. Trigonometry
4.12.1. Angles and Sides in Right Triangles
4.12.2. The Trigonometric Ratios
4.12.3. Calculating Trigonometric Ratios Using the Pythagorean Theorem
4.12.4. Calculating Side Lengths of Right Triangles Using Trigonometry
4.12.5. Calculating Angles in Right Triangles Using Trigonometry
4.12.6. Modeling With Trigonometry
4.12.7. The Reciprocal Trigonometric Ratios
4.12.8. Trigonometric Ratios in Similar Right Triangles
4.12.9. Trigonometric Functions of Complementary Angles
4.12.10. Special Trigonometric Ratios
4.12.11. Calculating the Area of a Right Triangle Using Trigonometry
4.12.12. Solving Multiple Right Triangles Using Trigonometry
5.
Solid Geometry
26 topics
5.13. Introduction to Solid Geometry
5.13.1. Identifying Three-Dimensional Shapes
5.13.2. Faces, Vertices, and Edges of Polyhedrons
5.13.3. Nets of Polyhedrons
5.13.4. Finding Surface Areas Using Nets
5.13.5. The Distance Formula in Three Dimensions
5.13.6. Euler's Formula for Polyhedra
5.13.7. The Five Platonic Solids
5.13.8. Surface Areas and Volumes of Similar Solids
5.14. Rectangular Solids and Pyramids
5.14.1. Volumes of Cubes
5.14.2. Surface Areas of Cubes
5.14.3. Face Diagonals of Cubes
5.14.4. Diagonals of Cubes
5.14.5. Volumes of Rectangular Solids
5.14.6. Surface Areas of Rectangular Solids
5.14.7. Diagonals of Rectangular Solids
5.14.8. Volumes of Pyramids
5.14.9. Surface Areas of Pyramids
5.15. Non-Polyhedrons
5.15.1. Volumes of Cylinders
5.15.2. Surface Areas of Cylinders
5.15.3. Volumes of Right Cones
5.15.4. Slant Heights of Right Cones
5.15.5. Surface Areas of Right Cones
5.15.6. Volumes of Spheres
5.15.7. Surface Areas of Spheres
5.15.8. Conical Frustums
5.15.9. Volumes of Revolution
6.
Probability & Combinatorics
31 topics
6.16. Introduction to Probability
6.16.1. Sets
6.16.2. Probability From Experimental Data
6.16.3. Sample Spaces and Events in Probability
6.16.4. Single Events in Probability
6.16.5. The Complement of an Event
6.16.6. Venn Diagrams in Probability
6.16.7. Geometric Probability
6.17. Compound Events in Probability
6.17.1. The Union of Sets
6.17.2. The Intersection of Sets
6.17.3. Compound Events in Probability From Experimental Data
6.17.4. Computing Probabilities for Compound Events Using Venn Diagrams
6.17.5. Computing Probabilities of Events Containing Complements Using Venn Diagrams
6.17.6. Computing Probabilities for Three Events Using Venn Diagrams
6.17.7. The Addition Law of Probability
6.17.8. Applying the Addition Law With Event Complements
6.17.9. Mutually Exclusive Events
6.18. Conditional Probability
6.18.1. Conditional Probabilities From Venn Diagrams
6.18.2. Conditional Probabilities From Tables
6.18.3. The Multiplication Law for Conditional Probability
6.18.4. The Law of Total Probability
6.18.5. Tree Diagrams for Dependent Events
6.18.6. Tree Diagrams for Dependent Events: Applications
6.18.7. Independent Events
6.18.8. Tree Diagrams for Independent Events
6.19. Combinatorics
6.19.1. The Rule of Sum and the Rule of Product
6.19.2. Factorials
6.19.3. Factorials in Variable Expressions
6.19.4. Ordering Objects
6.19.5. Permutations
6.19.6. Combinations
6.19.7. Computing Probabilities Using Combinatorics