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Geometry

Explore points, lines, angles, triangles, circles, area, volume, and geometric proofs.

12Categories25Topics100%Free

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Written and reviewed by the Study Mondo Education TeamLast updated

Course Overview

This Geometry course on Study Mondo covers 25 topics organized across 12 categories. Each topic includes detailed written explanations, worked examples, practice problems with step-by-step solutions, flashcards for review, and interactive lessons to help you master the material.

What You'll Learn

P

Points, Lines, and Angles

2 topics

T

Transformations and Congruence

5 topics

T

Triangles

7 topics

Q

Quadrilaterals and Polygons

2 topics

S

Similarity

1 topic

C

Circles

2 topics

R

Right Triangle Trigonometry

1 topic

A

Area and Perimeter

1 topic

C

Circles

3 topics

C

Coordinate Geometry

0 topics

T

Three-Dimensional Geometry

1 topic

S

Solid Geometry

0 topics

Start with any category below, or jump to a specific topic that you need help with.

Study tools

📝 Practice Test🎯 Unit Tests📅 Study schedules🃏 Flashcards📈 View Score Predictor📆 Daily question

Explore Related Topics

Jump into high-impact topics and keep your study momentum moving.

Angle RelationshipsParallel Lines and TransversalsRigid TransformationsTriangle Congruence TheoremsTranslationReflectionRotationTriangle Angle Sum Theorem
P
Points, Lines, and Angles2 topics

Angle Relationships

Complementary, supplementary, and vertical angles

Parallel Lines and Transversals

Angle relationships formed by parallel lines

T
Transformations and Congruence5 topics

Rigid Transformations

Perform translations, reflections, and rotations on the coordinate plane.

Triangle Congruence Theorems

Prove triangles congruent using SSS, SAS, ASA, AAS, and HL.

Translation

Slide a figure across the coordinate plane using vectors and coordinate rules — the gentlest rigid transformation.

Reflection

Flip a figure across a mirror line — the only basic rigid transformation that reverses orientation.

Rotation

Turn a figure about a center point by a specified angle — preserves distance, angles, and orientation.

T
Triangles7 topics

Triangle Angle Sum Theorem

The sum of angles in a triangle

Congruent Triangles

SSS, SAS, ASA, AAS, and HL theorems

Pythagorean Theorem

Relationships in right triangles

Similar Triangles

AA, SAS, and SSS similarity theorems

Special Right Triangles

45-45-90 and 30-60-90 triangles

Triangle Inequalities

Apply triangle inequality theorem

Special Segments in Triangles

Medians, altitudes, and angle bisectors

Q
Quadrilaterals and Polygons2 topics

Properties of Quadrilaterals

Parallelograms, rectangles, rhombi, squares, and trapezoids

Polygon Angle Sums

Interior and exterior angle formulas

S
Similarity1 topic

Similar Figures and Scale Factor

Understand similar figures, scale factors, and proportional reasoning in geometry.

C
Circles2 topics

Circle Basics

Parts of a circle and basic properties

Inscribed Angles

Angles with vertices on the circle

R
Right Triangle Trigonometry1 topic

Trigonometric Ratios

Use sine, cosine, and tangent to find missing sides and angles in right triangles.

A
Area and Perimeter1 topic

Area of Triangles and Quadrilaterals

Formulas for calculating area

C
Circles3 topics

Circle Theorems and Arc Relationships

Apply circle theorems involving central angles, inscribed angles, arcs, and chords.

Inscribed Angles

Work with angles inscribed in circles

Tangent Lines

Properties of tangent lines to circles

C
Coordinate Geometry0 topics

Topics coming soon for this category!

Check back later for comprehensive study materials.

T
Three-Dimensional Geometry1 topic

Surface Area and Volume of Solids

Calculate surface area and volume of prisms, cylinders, pyramids, cones, and spheres.

S
Solid Geometry0 topics

Topics coming soon for this category!

Check back later for comprehensive study materials.