Description 1. Addition and Subtraction of Fractions 2. Triangles 3. Addition and Subtraction of Decimals 4. Quadrilaterals 5. Line Graphs 6. Polygons [Concept Book] 1. Concept Learning: Textbook concepts are broken down and organized in a dictionary-like format for easy understanding. Basic practice problems are also provided so learners can immediately apply what they've just learned. 2. Concept Practice: Essential problems from textbooks and workbooks help solidify understanding of each concept. 3. Mastering Problem Types: A 1:2 learning system (representative problem type + practice problem 1 + practice problem 2) helps students fully master each problem type. 4. Unit Review: Allows students to check their overall understanding of each unit and prepare for real tests. [Workbook] Provides customized practice problems for each concept covered in the Concept Book, helping students reinforce their understanding and complete their mastery of the material. [Answers and Explanations] Quick answers are provided for convenient grading, along with detailed explanations and abundant supplementary materials to support problem-solving. "The Answer to Mastering Math Concepts = Ssen" The foundation of math lies in mastering concepts. Building strong skills requires working steadily through each stage, starting from the basics. helps students understand concepts quickly and easily with the Concept Book, then reinforce and solidify their understanding with the Workbook. Through this repeated learning system of Concept Book + Workbook, students can fully understand math concepts and truly make them their own. is the essential first concept-based textbook for building strong math skills.