Geometry for Self-Preparation . 9th grade . The manual for students of institutions of general secondary education" is an indispensable assistant for schoolchildren who seek to deepen their knowledge in the field of geometry and prepare for exams. Created by a team of authors, this manual offers readers not only theoretical foundations, but also practical tasks that will help to consolidate the material studied. Geometry is not just a set of formulas and theorems, it is a whole world in which lines, shapes and spaces intersect. In this book you will find accessible explanations of complex concepts that often baffle even the most diligent students. Each chapter begins with a summary of the theory, followed by a variety of tasks that will help develop logical thinking and spatial perception. The manual covers all key topics, including the properties of geometric shapes, theorems, as well as practical applications of geometry in real life. This book will be especially useful for students of the 9th grade, as well as for anyone who wants to refresh their knowledge of geometry. It is suitable both for self-study and for use in lessons. Teachers will also find in the manual useful materials for preparing for classes and exams. Students preparing for the exam or other exams will be able to use this manual to systematize knowledge and confident preparation for tests. The topics raised in the book go beyond the simple study of geometry. The authors focus on the importance of logical thinking, analytical skills and problem solving, which is an integral part of modern education. The book helps to develop not only mathematical abilities, but also critical thinking, which is especially important in a rapidly changing world. The style of the authors is distinguished by clarity and accessibility of presentation, which makes the material understandable even for those who are not natural mathematicians. Each task is accompanied by detailed solutions, which allows readers to independently test their knowledge and understand where they made mistakes. This guide is not just a textbook, but a real guide to the world of geometry, which inspires the study and discovery of new horizons. If you are looking for additional materials on geometry, pay attention to books such as "Geometry. 9th Grade . Textbook" from other authors or "Geometry. Preparing for the exam" - they will help you deepen your knowledge and prepare for exams. Finally, "Geometry for self-preparation. 9th grade . The manual for students of institutions of general secondary education" is not just a manual, but a whole tool for developing mathematical skills and self-confidence. This book will be your reliable companion on the way to success in the study of geometry, and may open up new horizons for you in the world of mathematics. Do not miss the chance to take a step towards your future with this fascinating and useful book!