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High school geometry

#### Course content

#### Geometry foundations

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#### Transformations

#### Congruence

#### Similarity

#### Right triangles & trigonometry

#### Solid geometry

#### Analytic geometry

#### Circles

Free

282 Lessons

Intro to Euclidean geometry

Euclid as the father of geometry

Terms & labels in geometry

Lines, line segments, & rays

Specifying planes in three dimensions

Geometric definitions example

Angles

Measuring angles in degrees

Measuring angles using a protractor

Measuring angles using a protractor 2

Acute, right, & obtuse angles

Vertical angles

Equation practice with vertical angles

Complementary & supplementary angles

Equation practice with complementary angles

Equation practice with supplementary angles

Angles, parallel lines, & transversals

Parallel & perpendicular lines

Missing angles with a transversal

Measures of angles formed by a transversal

Proving angles are congruent

Polygons

Angles in a triangle sum to 180° proof

Triangle exterior angle example

Worked example: Triangle angles (intersecting lines)

Worked example: Triangle angles (diagram)

Triangle angle challenge problem 2

Sum of interior angles of a polygon

Sum of the exterior angles of a polygon

Triangle inequality theorem

Intro to quadrilateral

Quadrilateral properties

Kites as a geometric shape

Quadrilateral types

Proof: Opposite sides of a parallelogram

Proof: Opposite angles of a parallelogram

Area

Perimeter & area

Area of a triangle

Area of a parallelogram

Area of trapezoids

Area of kites

Area of a triangle on a grid

Area of a quadrilateral on a grid

Area of composite shapes

Perimeter & area of composite shapes

Challenge problems: perimeter & area

Radius, diameter, circumference & π

Area of a circle

Radius & diameter from circumference

Area of a circle intuition

Intro to nets of polyhedra

Surface area using a net: rectangular prism