Plane Geometry
Study points, lines, angles, proofs, triangles, polygons, area, volume, circles, and coordinate geometry.
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About this course
Quiz and transcript rule: quizzes unlock after the one-time $10 Quiz Proctor Fee is paid for this course. Students must complete all published Plane Geometry quizzes with a score of 90% or better for the course to appear as completed on their transcript.
One lesson at a time
Your learning journey
124 lessons · 124 assessments
01Introduction to GeometryVideo lesson · Quiz
Build foundational geometry skills from diagrams, definitions, measurements, and relationships.
02Lines, Rays, Line Segments, Points, Angles, Union & Intersection - Geometry Basic IntroductionVideo lesson · Quiz
Use coordinate and line relationships to analyze points, segments, rays, slopes, distances, and planes.
03Acute Obtuse Right & Straight Angles - Complementary and Supplementary AnglesVideo lesson · Quiz
Measure, classify, convert, and solve angle relationships.
04Decimal Degrees to DMS Formula - Converting Degrees Minutes and Seconds to Decimal - TrigonometryVideo lesson · Quiz
Measure, classify, convert, and solve angle relationships.
05Clock Aptitude Reasoning Tricks & Problems - Finding Angle Between The Hands of a Clock Given TimeVideo lesson · Quiz
Measure, classify, convert, and solve angle relationships.
06Angle Bisector Theorem - Midpoints & Line SegmentsVideo lesson · Quiz
Use coordinate and line relationships to analyze points, segments, rays, slopes, distances, and planes.
07Converse, Inverse, & Contrapositive - Conditional & Biconditional Statements, Logic, GeometryVideo lesson · Quiz
Use algebraic, logical, congruence, and probability reasoning inside geometry problems.
08Probability With Geometry - Length, Area & VolumeVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
09Perpendicular Lines, Slope, Rays, and Segments | GeometryVideo lesson · Quiz
Use coordinate and line relationships to analyze points, segments, rays, slopes, distances, and planes.
10Complementary and Supplementary AnglesVideo lesson · Quiz
Measure, classify, convert, and solve angle relationships.
11Addition and Subtraction Property of EqualityVideo lesson · Quiz
Use algebraic, logical, congruence, and probability reasoning inside geometry problems.
12Multiplication and Division Property of EqualityVideo lesson · Quiz
Use algebraic, logical, congruence, and probability reasoning inside geometry problems.
13Transitive Property of Congruence & Substitution Property of EqualityVideo lesson · Quiz
Use algebraic, logical, congruence, and probability reasoning inside geometry problems.
14TrianglesVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
15Parallel and Perpendicular Lines, Transversals, Alternate Interior Angles, Alternate Exterior AnglesVideo lesson · Quiz
Use coordinate and line relationships to analyze points, segments, rays, slopes, distances, and planes.
16Two Column Proofs of Congruent Segments - Midpoints, Substitution, Division & Addition PropertyVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
17Geometry, Two Column Proofs of Angles - Addition, Substitution & Transitive PropertyVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
18Triangle Congruence Theorems, Two Column Proofs, SSS, SAS, ASA, AAS Postulates, Geometry ProblemsVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
19CPCTC Geometry Proofs Made Easy, Triangle Congruence - SSS, SAS, ASA, & AAS, Two Colmn ProofsVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
20Median of a Triangle Formula, Example Problems, Properties, Definition, Geometry, Midpoint & CentroiVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
21Altitude of a Triangle - Finding The OrthocenterVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
22Two Column Proofs - Triangles, Medians and AltitudesVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
23Geometry Proofs - Isosceles Triangles - SAS & AASVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
24Angle Side / Base-Angle Theorem - Two Column ProofsVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
25Hypotenuse Leg Theorem - HL Postulate - Two Column ProofsVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
26Detour Proofs - Double Triangle CongruenceVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
27Midpoint FormulaVideo lesson · Quiz
Use coordinate and line relationships to analyze points, segments, rays, slopes, distances, and planes.
28Missing Diagrams With Two Column ProofsVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
29Right Angle Theorem - SSS & AAS - Two Column ProofsVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
30Perpendicular Bisector of a Line Segment and TriangleVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
31Altitudes, Medians, Midpoints, Angle & Perpendicular BisectorsVideo lesson · Quiz
Use coordinate and line relationships to analyze points, segments, rays, slopes, distances, and planes.
32Finding The Slope Given Two Points - Parallel & Perpendicular Lines - Altitudes & Medians | GeometryVideo lesson · Quiz
Use coordinate and line relationships to analyze points, segments, rays, slopes, distances, and planes.
33Indirect Proofs, Practice Problems, Two Column Proofs - GeometryVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
34Proving Parallel Lines With Two Column Proofs - Geometry, Practice ProblemsVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
35Exterior Angle Theorem For Triangles, Practice Problems - GeometryVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
36Exterior Angle Inequality Theorem With Two Column Proofs - GeometryVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
37PolygonsVideo lesson · Quiz
Analyze polygons and quadrilaterals using sides, angles, diagonals, and special properties.
38How To Calculate The Interior Angles and Exterior Angles of a Regular PolygonVideo lesson · Quiz
Analyze polygons and quadrilaterals using sides, angles, diagonals, and special properties.
39Quadrilaterals - GeometryVideo lesson · Quiz
Analyze polygons and quadrilaterals using sides, angles, diagonals, and special properties.
40Parallelograms - GeometryVideo lesson · Quiz
Analyze polygons and quadrilaterals using sides, angles, diagonals, and special properties.
41Rectangles - Properties of Parallelograms, Special Quadrilaterals - GeometryVideo lesson · Quiz
Analyze polygons and quadrilaterals using sides, angles, diagonals, and special properties.
42Isosceles TrapezoidsVideo lesson · Quiz
Analyze polygons and quadrilaterals using sides, angles, diagonals, and special properties.
43Rhombus, Basic Introduction - GeometryVideo lesson · Quiz
Analyze polygons and quadrilaterals using sides, angles, diagonals, and special properties.
44Kites, Basic Introduction, GeometryVideo lesson · Quiz
Analyze polygons and quadrilaterals using sides, angles, diagonals, and special properties.
45Proving Parallelograms With Two Column Proofs - GeometryVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
46Proving a Quadrilateral Is a Kite - Two Column Proofs - GeometryVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
47Two Column Proofs - Proving a Parallelogram Is a Rhombus - GeometryVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
48Two Column Proofs - Proving Isosceles Trapezoids - GeometryVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
49Two Column Proofs With Parallelograms, Isosceles Trapezoids, Rhombuses, and Kites - GeometryVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
50Skew Lines, Perpendicular & Parallel Lines & Planes, Intersecting Lines & TransversalsVideo lesson · Quiz
Use coordinate and line relationships to analyze points, segments, rays, slopes, distances, and planes.
51Points, Lines, Planes, Segments, & Rays - Collinear vs Coplanar Points - GeometryVideo lesson · Quiz
Use coordinate and line relationships to analyze points, segments, rays, slopes, distances, and planes.
52Triangles - Basic Introduction, GeometryVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
53Number of Diagonals In a Regular Polygon - GeometryVideo lesson · Quiz
Analyze polygons and quadrilaterals using sides, angles, diagonals, and special properties.
54Ratios and Proportions, Arithmetic & Geometric Mean, Means Extremes Theorem - Geometry ProblemsVideo lesson · Quiz
Build foundational geometry skills from diagrams, definitions, measurements, and relationships.
55Similar TrianglesVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
56Similar Triangles and Figures, Enlargement Ratios & Proportions Geometry Word ProblemsVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
57Triangle Similarity - AA SSS SAS & AAA Postulates, Proving Similar Triangles, Two Column ProofsVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
58Triangle Proportionality Theorem, Side Splitter Theorem & Angle Bisector Theorem - GeometryVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
59Altitude on Hypotenuse Theorem - Geometry Practice ProblemsVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
60Pythagorean TheoremVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
61Distance FormulaVideo lesson · Quiz
Use coordinate and line relationships to analyze points, segments, rays, slopes, distances, and planes.
62How To Find The Distance Between Two PointsVideo lesson · Quiz
Use coordinate and line relationships to analyze points, segments, rays, slopes, distances, and planes.
63How To Find The Distance Between 2 Points In 3D SpaceVideo lesson · Quiz
Compute and interpret measurements for three-dimensional solids.
64Special Right Triangles - 30 60 90 - Geometry & Trigonometry | SAT MathVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
65Special Right Triangles - 45 45 90 - Trigonometry & Geometry | SAT MathVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
66Trigonometric RatiosVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
67Angle of Elevation and Depression Word Problems Trigonometry, Finding Sides, Angles, Right TrianglesVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
68How To Calculate The Missing Side Length of a TriangleVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
69How To Calculate The Missing Angle In a TriangleVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
70How To Solve Two Triangle Trigonometry ProblemsVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
71How To Find The Area of a Rectangle | MathVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
72Area and PerimeterVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
73Area of a SquareVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
74Area of a Triangle, Given 3 Sides, Heron's FormulaVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
75How To Calculate The Height of a Triangle Using Heron's FormulaVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
76Area of a TrapezoidVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
77Area of a ParallelogramVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
78Area of a RhombusVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
79How To Calculate The Area Between Two SquaresVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
80Area of a Rectangle, Triangle, Circle & Sector, Trapezoid, Square, Parallelogram, Rhombus, GeometryVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
81Area and Perimeter of Irregular Shapes - Tons of Examples!Video lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
82How To Calculate Square FootageVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
83Area of a KiteVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
84Area of an Equilateral TriangleVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
85Area of Regular Polygons - Hexagons, Pentagons, & Equilateral Triangles With Inscribed CirclesVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
86Circles - Area, Circumference, Radius & Diameter Explained!Video lesson · Quiz
Work with circles using radius, diameter, circumference, area, arcs, chords, tangents, secants, and angle theorems.
87Circles In Geometry, Basic Introduction - Circumference, Area, Arc Length, Inscribed Angles & ChordsVideo lesson · Quiz
Work with circles using radius, diameter, circumference, area, arcs, chords, tangents, secants, and angle theorems.
88Area of Shaded Region - Circles, Rectangles, Triangles, & Squares - GeometryVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
89Geometry - Area Math ProblemVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
903D Shapes - Faces, Edges, and Vertices - Euler's Formula - GeometryVideo lesson · Quiz
Compute and interpret measurements for three-dimensional solids.
91How To Find The Volume of a Rectangular Prism - GeometryVideo lesson · Quiz
Compute and interpret measurements for three-dimensional solids.
92How To Find The Surface Area of a Rectangular Prism - GeometryVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
93Rectangular Prism - Volume, Surface Area and Diagonal Length, Rectangles, GeometryVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
94Volume of a Triangular PrismVideo lesson · Quiz
Compute and interpret measurements for three-dimensional solids.
95Surface Area of a Triangular Prism - Lateral Area, GeometryVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
96Triangular Prism - Volume, Surface Area, Base and Lateral Area Formula, Basic GeometryVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
97Surface Area of a Hexagonal Prism - Volume & Lateral Area - GeometryVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
98Volume of a CubeVideo lesson · Quiz
Compute and interpret measurements for three-dimensional solids.
99Surface Area of a CubeVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
100Diagonal Length of a CubeVideo lesson · Quiz
Compute and interpret measurements for three-dimensional solids.
101Volume of a PyramidVideo lesson · Quiz
Compute and interpret measurements for three-dimensional solids.
102Surface Area of a Pyramid - Lateral Area - GeometryVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
103Surface Area of a Pyramid & Volume of Square Pyramids & Triangular PyramidsVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
104Volume of a CylinderVideo lesson · Quiz
Compute and interpret measurements for three-dimensional solids.
105Surface Area of a Cylinder With Lateral AreaVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
106Volume of a SphereVideo lesson · Quiz
Compute and interpret measurements for three-dimensional solids.
107Surface Area of a SphereVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
108Volume of a ConeVideo lesson · Quiz
Compute and interpret measurements for three-dimensional solids.
109Surface Area of a Cone with Lateral Area - geometryVideo lesson · Quiz
Calculate area and perimeter for common and composite plane figures.
110Circles - Chords, Radius & Diameter - Basic Introduction - GeometryVideo lesson · Quiz
Work with circles using radius, diameter, circumference, area, arcs, chords, tangents, secants, and angle theorems.
111Central Angles, Circle Arcs, Angle Measurement, Major Arcs vs Minor Arcs, Chords - GeometryVideo lesson · Quiz
Work with circles using radius, diameter, circumference, area, arcs, chords, tangents, secants, and angle theorems.
112Tangent Lines & Secant Lines of Circles, Walk Around Problem - GeometryVideo lesson · Quiz
Work with circles using radius, diameter, circumference, area, arcs, chords, tangents, secants, and angle theorems.
113Circles, Angle Measures, Arcs, Central & Inscribed Angles, Tangents, Secants & Chords - GeometryVideo lesson · Quiz
Work with circles using radius, diameter, circumference, area, arcs, chords, tangents, secants, and angle theorems.
114Tangent Tangent Angle Theorems - Circles & Arc Measures - GeometryVideo lesson · Quiz
Work with circles using radius, diameter, circumference, area, arcs, chords, tangents, secants, and angle theorems.
115Inscribed Polygons and Circumscribed Polygons, Circles - GeometryVideo lesson · Quiz
Work with circles using radius, diameter, circumference, area, arcs, chords, tangents, secants, and angle theorems.
116Power Theorems - Chords, Secants & Tangents - Circle Theorems - GeometryVideo lesson · Quiz
Work with circles using radius, diameter, circumference, area, arcs, chords, tangents, secants, and angle theorems.
117Circle TheoremsVideo lesson · Quiz
Work with circles using radius, diameter, circumference, area, arcs, chords, tangents, secants, and angle theorems.
118Two Column Proofs With Circles - GeometryVideo lesson · Quiz
Use givens, definitions, properties, and theorems to build a clear geometry proof.
119Circles - GeometryVideo lesson · Quiz
Work with circles using radius, diameter, circumference, area, arcs, chords, tangents, secants, and angle theorems.
120Incenter, Circumcenter, Orthocenter & Centroid of a Triangle - GeometryVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
121Distance Between a Point and a Line In 2D & 3D - GeometryVideo lesson · Quiz
Compute and interpret measurements for three-dimensional solids.
122Area of a Triangle With Vertices - GeometryVideo lesson · Quiz
Analyze triangles using side lengths, angle relationships, congruence, similarity, right-triangle rules, and trig ratios.
123Coordinate Geometry, Basic Introduction, Practice ProblemsVideo lesson · Quiz
Use coordinate and line relationships to analyze points, segments, rays, slopes, distances, and planes.
124Geometry Final Exam Review - Study GuideVideo lesson · Quiz
Build foundational geometry skills from diagrams, definitions, measurements, and relationships.
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Notes & resources
124 resources across the course. Open individual lessons to find the available notes and supporting materials.
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