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Introduction to GeometryFundamentals of geometry, including angles, triangle similarity and congruence, complicated area problems, mastering the triangle, special quadrilaterals, polygons, the art of angle chasing, power of a point, 3dimensional geometry, transformations, analytic geometry, basic trigonometry, geometric proof, and more. 
24 weeks 
24 weeks ARE YOU READY? DO YOU NEED THIS? SYLLABUS 
Schedule
Sunday
Sep 26  Apr 3 
7:30  9:00 PM ET
Sep 26  Apr 3
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Ekaterina Machavariani 
$595
$656 w/books

$595
CLOSED
With Books $656

Thursday
Oct 21  Apr 21 
7:30  9:00 PM ET
Oct 21  Apr 21
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Achilleas Sinefakopoulos 
$595
$656 w/books

$595
ENROLL
With Books $656

Monday
Nov 8  May 9 
7:30  9:00 PM ET
Nov 8  May 9
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Valentin Vornicu 
$595
$656 w/books

$595
ENROLL
With Books $656

Friday
Dec 3  May 27 
7:30  9:00 PM ET
Dec 3  May 27
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Homero Renato Gallegos Ruiz 
$595
$656 w/books

$595
ENROLL
With Books $656

Tuesday
Dec 7  May 31 
7:30  9:00 PM ET
Dec 7  May 31
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Maria Mendes 
$595
$656 w/books

$595
ENROLL
With Books $656

Spring 2022  This course will be offered in Spring 2022. Click here to join our mailing list to be notified when the course schedule is available. 
AoPS Holidays
There are no classes October 31, November 22–28, and December 20–January 2.
Who Should Take?
This is the most challenging of our Introduction series of classes. We recommend that students complete our Introduction to Algebra B course, or are able to pass the Introduction to Algebra B posttest, prior to taking Introduction to Geometry.Lessons
Lesson 1  Angles 
Lesson 2  Triangle Angles and Congruent Triangles 
Lesson 3  Isosceles & Equilateral Triangles, Perimeter, and Area 
Lesson 4  Similar Triangles 
Lesson 5  Similar Triangles and Right Triangles 
Lesson 6  More Right Triangles! 
Lesson 7  Special Parts of a Triangle 
Lesson 8  Special Parts of a Triangle, Continued! 
Lesson 9  Quadrilaterals 
Lesson 10  More Quadrilaterals 
Lesson 11  Polygons 
Lesson 12  Geometric Inequalities 
Lesson 13  Introduction to Circles 
Lesson 14  Circles and Angles 
Lesson 15  Tangents 
Lesson 16  Power of a Point 
Lesson 17  3D Geometry Part 1 
Lesson 18  3D Geometry Part 2 
Lesson 19  Transformations 
Lesson 20  Analytic Geometry 
Lesson 21  More Analytic Geometry 
Lesson 22  Basic Trigonometry 
Lesson 23  Problems! 
Lesson 24  More Problems! 
Required Textbook
Introduction to Geometry
A full course in challenging geometry for students in grades 710, including topics such as similar
triangles, congruent triangles, quadrilaterals, polygons, circles, funky
areas, power of a point, threedimensional geometry, transformations, introductory trigonometry, and
more.
