Download NCERT and Exemplar books class 8 PDF format. Try to solve the questions given in NCERT exercises yourself first at your level best and after that switch NCERT Solutions for help if any. It will improve your maths knowledge.
NCERT Book

Chapter 1: Rational Numbers

Chapter 2: Linear Equations in one Variable

Chapter 3: Understanding Quadrilaterals

Chapter 4: Practical Geometry

Chapter 5: Data Handling

Chapter 6: Square and Square Roots

Chapter 7: Cube and Cube Roots

Chapter 8: Comparing Quantities

Chapter 9: Algebraic Expressions and Identities

Chapter 10: Visualizing Solid Shapes

Chapter 11: Mensuration

Chapter 12: Exponents and Powers

Chapter 13: Direct and Inverse Proportions

Chapter 14: Factorization

Chapter 15: Introduction to Graphs

Chapter 16: Playing with Numbers

Answers
NCERT Exemplar

Chapter 1: Rational Numbers

Chapter 2: Linear Equations in one Variable

Chapter 3: Understanding Quadrilaterals

Chapter 4: Practical Geometry

Chapter 5: Data Handling

Chapter 6: Square and Square Roots

Chapter 7: Cube and Cube Roots

Chapter 8: Comparing Quantities

Chapter 9: Algebraic Expressions and Identities

Chapter 10: Visualizing Solid Shapes

Chapter 11: Mensuration

Chapter 12: Exponents and Powers

Chapter 13: Direct and Inverse Proportions

Chapter 14: Factorization

Chapter 15: Introduction to Graphs

Chapter 16: Playing with Numbers

Answers