Geometry (TX TEKS)
Learn high school geometry—reasoning with two-dimensional and three-dimensional figures visually and algebraically. This course aligns with TX TEKS standards.
12 units210 videos20 hours
Learn it live with a class on Puzzicle · Teachers: use it with your class
Unit 1: Introduction to logic and Euclidean geometry
Undefined terms and definitions
Postulates, conjectures, and theorems
Conditional statements
Unit 2: Coordinate geometry
Dividing line segments in one dimension
Distance and midpoints
Dividing line segments
Parallel and perpendicular lines on the coordinate plane
Equations of parallel and perpendicular lines
Parallel and perpendicular lines in figures
Unit 3: Transformations in the plane
Symmetry
Composing transformations
Algebraic rules for basic transformations
Translations: graph to algebraic rule ✓ Check-ins2:21
Translations: description to algebraic rule ✓ Check-ins1:29
Rotations: graph to algebraic rule ✓ Check-ins4:07
Rotations: description to algebraic rule ✓ Check-ins4:15
Reflections: graph to algebraic rule ✓ Check-ins2:28
Reflections: description to algebraic rule ✓ Check-ins ✎ Fixed a slip2:39
Representing dilations algebraically, k less than 1 ✓ Check-ins3:28
Representing dilations algebraically, k greater than 1 ✓ Check-ins3:56
Building advanced transformations
Rotating algebraically about a point ✓ Check-ins ✎ Fixed a slip7:35
Dilating algebraically about a point ✓ Check-ins ✎ Fixed a slip5:15
Reflecting over y=x ✓ Check-ins2:59
Reflecting over y=-x ✓ Check-ins4:04
Graphing a non similar pre image algebraically ✓ Check-ins3:39
Composing transformations ✓ Check-ins5:17
Unit 4: Relationships of lines and transversals
Line and angle proofs
Unit 5: Congruence in triangles
Rigid transformations
Triangle inequality theorem
Triangle congruence from transformations
Proving the SSS triangle congruence criterion using transformations ✓ Check-ins5:47
Proving the SAS triangle congruence criterion using transformations ✓ Check-ins4:31
Proving the ASA and AAS triangle congruence criteria using transformations ✓ Check-ins7:24
Why SSA isn't a congruence postulate/criterion ✓ Check-ins7:24
Congruent triangles
Theorems concerning triangle properties
Unit 6: Similarity in triangles
Definitions of similarity
Introduction to triangle similarity
Solving similar triangles
Angle bisector theorem
Special segments in triangles
Exploring medial triangles ✓ Check-ins11:33
Proof: Parallel lines divide triangle sides proportionally ✓ Check-ins6:32
Proving triangle medians intersect at a point ✓ Check-ins7:22
Dividing triangles with medians ✓ Check-ins7:46
Centroid & median proof ✓ Check-ins ✎ Fixed a slip6:56
Median, centroid example ✓ Check-ins9:00
Solving problems with similar and congruent triangles
Proving relationships using similarity
Solving modeling problems with similar & congruent triangles
Unit 7: Relationships of right triangles, including trigonometry
Pythagorean theorem
Pythagorean theorem proofs
Special right triangles
Ratios in right triangles
Introduction to the trigonometric ratios
Solving for a side in a right triangle using the trigonometric ratios
Modeling with right triangles
Unit 8: Relationships of circles, including radian measure and equations of circles
Circle basics
Arc measure
Inscribed shapes problem solving
Proofs with inscribed shapes
Properties of 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
Properties of chords
Properties of secants
Constructing regular polygons inscribed in circles
Constructing circumcircles and incircles
Constructing a line tangent to a circle
Introduction to radians
Standard equation of a circle
Graphs and equations of circles
Unit 9: Relationships of two- and three-dimensional figures
Classifying figures
Polygon angle sum theorems
Two-dimensional vs. three-dimensional objects
Unit 10: Measurement of two-dimensional figures
Scaling 2D figures
Arc length (from degrees)
Arc length (from radians)
Regular polygons
Unit 11: Measurement of three-dimensional figures
RIght triangles in 3D figures
Surface area
Surface area of composite figures
Cavalieri's principle
Volume
Volume and surface area of frustums
Scaling three-dimensional figures
Unit 12: Probability
Multiplication rule for probabilities
Conditional probability
Dependent events
Permutations
Combinations
Area-based probability
Learn this with a class
With a class on Puzzicle this course runs as a timetable of live study parties: your batch watches together and answers the check-ins, sometimes with a teacher leading.
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