Geometry (Eureka Math/EngageNY)
Learn Geometry aligned to the Eureka Math/EngageNY curriculum —transformations, congruence, similarity, and more.
5 units175 videos17 hours
Learn it live with a class on Puzzicle · Teachers: use it with your class
Unit 1: Module 1: Congruence, proof, and constructions
Topic A: Basic constructions
Geometric constructions: circle-inscribed regular hexagon ✓ Check-ins3:41
Geometric constructions: angle bisector ✓ Check-ins2:17
Geometric constructions: perpendicular line through a point on the line ✓ Check-ins1:12
Geometric constructions: perpendicular bisector ✓ Check-ins1:26
Incenter and incircles of a triangle ✓ Check-ins ✎ Fixed a slip7:58
Geometric constructions: triangle-inscribing circle ✓ Check-ins2:33
Geometric constructions: triangle-circumscribing circle ✓ Check-ins2:22
Proof: Triangle altitudes are concurrent (orthocenter) ✓ Check-ins ✎ Fixed a slip10:01
Topic B: Lesson 6: Solve for unknown angles—angles and lines at a point
Topic B: Lesson 7: Solve for unknown angles—transversals
Topic B: Lesson 8: Solve for unknown angles—angles in a triangle
Topic B: Lessons 9-11: Unknown angle proofs
Topic C: Lesson 12: Transformations—The next level
Topic C: Lesson 13: Rotations
Topic C: Lesson 14: Reflections
Topic C: Lesson 15: Rotations, reflections, and symmetry
Topic C: Lesson 16: Translations
Topic C: Lessons 17-21: Applications of transformations
Topic D: Lessons 22-25: Congruence criteria
Triangle congruence postulates/criteria ✓ Check-ins13:28
Why SSA isn't a congruence postulate/criterion ✓ Check-ins7:24
Determining congruent triangles ✓ Check-ins7:28
Proofs concerning isosceles triangles ✓ Check-ins9:03
Proofs concerning equilateral triangles ✓ Check-ins6:29
Isosceles & equilateral triangles problems ✓ Check-ins6:27
Corresponding angles in congruent triangles ✓ Check-ins4:35
Topic D: Lessons 26-27: Triangle congruency proofs
Topic E: Proving properties of geometric figures
Proof: Opposite sides of a parallelogram ✓ Check-ins8:30
Proof: Diagonals of a parallelogram ✓ Check-ins9:06
Proof: Opposite angles of a parallelogram ✓ Check-ins4:08
Proof: The diagonals of a kite are perpendicular ✓ Check-ins11:06
Proof: Rhombus diagonals are perpendicular bisectors ✓ Check-ins4:04
Proof: Rhombus area ✓ Check-ins5:07
Triangle medians & centroids ✓ Check-ins ✎ Fixed a slip8:59
Triangle medians and centroids (2D proof) ✓ Check-ins15:15
Dividing triangles with medians ✓ Check-ins7:46
Exploring medial triangles ✓ Check-ins11:33
Centroid & median proof ✓ Check-ins ✎ Fixed a slip6:56
Median, centroid example ✓ Check-ins9:00
Unit 2: Module 2: Similarity, proof, and trigonometry
Topic B: Dilations
Topic C: Lessons 12-14: Similarity intro
Topic C: Lessons 15-17: Triangle similarity
Topic C: Lessons 18-20: Similarity applications
Intro to angle bisector theorem ✓ Check-ins8:35
Using the angle bisector theorem ✓ Check-ins3:04
Using similar & congruent triangles ✓ Check-ins10:07
Challenging similarity problem ✓ Check-ins9:53
Geometry word problem: the golden ratio ✓ Check-ins8:23
Geometry word problem: Earth & Moon radii ✓ Check-ins6:23
Geometry word problem: a perfect pool shot ✓ Check-ins6:49
Topic D: Applying similarity to right triangles
Topic E: Lessons 25-26: Trigonometry intro
Topic E: Lesson 27: Sine and cosine of complementary angles and special angles
Sine & cosine of complementary angles ✓ Check-ins4:15
Using complementary angles ✓ Check-ins4:05
Trig word problem: complementary angles ✓ Check-ins5:44
Special right triangles intro (part 1) ✓ Check-ins ✎ Fixed a slip9:30
Special right triangles intro (part 2) ✓ Check-ins ✎ Fixed a slip9:39
30-60-90 triangle example problem ✓ Check-ins6:40
Special right triangles proof (part 1) ✓ Check-ins6:59
Special right triangles proof (part 2) ✓ Check-ins5:42
Topic E: Lessons 28-31: Trigonometry applications
Topic E: Lessons 32-33: Laws of sines and cosines
Solving for a side with the law of sines ✓ Check-ins5:58
Solving for an angle with the law of sines ✓ Check-ins5:34
Proof of the law of sines ✓ Check-ins6:34
Solving for a side with the law of cosines ✓ Check-ins4:38
Solving for an angle with the law of cosines ✓ Check-ins6:41
Proof of the law of cosines ✓ Check-ins9:26
Trig word problem: stars ✓ Check-ins6:00
Unit 3: Module 3: Extending to three dimensions
Topic A: Area
Topic B: Lessons 5-9: Volume properties
Topic B: Lessons 10-13: Volume formulas
Volume of triangular prism & cube ✓ Check-ins3:56
Cylinder volume & surface area ✓ Check-ins8:07
Volume of a cone ✓ Check-ins5:44
Volume of a sphere ✓ Check-ins2:35
Cavalieri's principle in 3D ✓ Check-ins4:56
Volume of pyramids intuition ✓ Check-ins8:29
Volumes of cones intuition ✓ Check-ins5:42
Using related volumes ✓ Check-ins6:16
Unit 4: Module 4: Connecting algebra and geometry through coordinates
Topic A: Rectangular and triangular regions defined by inequalities
Topic B: Perpendicular and parallel lines in the Cartesian plane
Parallel & perpendicular lines intro ✓ Check-ins2:08
Parallel & perpendicular lines from graph ✓ Check-ins7:26
Parallel lines from equation ✓ Check-ins3:48
Parallel lines from equation (example 2) ✓ Check-ins3:03
Parallel lines from equation (example 3) ✓ Check-ins2:42
Perpendicular lines from equation ✓ Check-ins3:29
Writing equations of perpendicular lines ✓ Check-ins3:01
Writing equations of perpendicular lines (example 2) ✓ Check-ins1:45
Proof: parallel lines have the same slope ✓ Check-ins5:49
Proof: perpendicular lines have opposite reciprocal slopes ✓ Check-ins8:55
Topic C: Perimeters and areas of polygonal regions in the Cartesian plane
Topic D: Partitioning and extending segments and parameterization of lines
Unit 5: Module 5: Circles with and without coordinates
Topic A: Central and inscribed angles
Inscribed angles ✓ Check-ins1:20
Inscribed angle theorem proof ✓ Check-ins14:16
Proof: Right triangles inscribed in circles ✓ Check-ins5:35
Inscribed shapes: find diameter ✓ Check-ins2:33
Inscribed shapes: angle subtended by diameter ✓ Check-ins5:49
Inscribed shapes: find inscribed angle ✓ Check-ins2:10
Inscribed quadrilaterals proof ✓ Check-ins3:56
Solving inscribed quadrilaterals ✓ Check-ins4:58
Geometric constructions: circle-inscribed square ✓ Check-ins2:47
Geometric constructions: circle-inscribed equilateral triangle ✓ Check-ins3:28- Geometric constructions: circle-inscribed regular hexagon ✓ Check-ins3:41
Proof: radius is perpendicular to a chord it bisects ✓ Check-ins8:19
Proof: perpendicular radius bisects chord ✓ Check-ins3:53
Topic B: Lessons 7-8: Angles and arcs
Topic B: Lessons 9-10: Arc length and sector area
Arc length from subtended angle ✓ Check-ins4:58
Subtended angle from arc length ✓ Check-ins2:18
Intro to radians ✓ Check-ins10:51
Radians & degrees ✓ Check-ins7:12
Degrees to radians ✓ Check-ins7:02
Radians to degrees ✓ Check-ins3:20
Arc length as fraction of circumference ✓ Check-ins2:59
Arc length from subtended angle: radians ✓ Check-ins2:39
Area of a sector ✓ Check-ins2:26
Topic C: Secants and tangents
Proof: Radius is perpendicular to tangent line ✓ Check-ins8:41
Proof: Segments tangent to circle from outside point are congruent ✓ Check-ins3:56
Tangents of circles problem (example 1) ✓ Check-ins4:37
Tangents of circles problem (example 2) ✓ Check-ins3:47
Tangents of circles problem (example 3) ✓ Check-ins2:34
Geometric constructions: circle tangent ✓ Check-ins5:50
Geometric constructions: circle tangent (example 2) ✓ Check-ins5:35
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