Chapter 8: Algebraic Expressions and Identities

Math • Class 8

Download PDF

Loading PDF...

Chapter Analysis

Intermediate10 pages • English

Quick Summary

This chapter introduces students to algebraic expressions, covering the addition, subtraction, and multiplication of these expressions. It explains concepts such as monomials, binomials, trinomials, and polynomials, along with the application of laws such as the distributive law in calculations. Students learn to multiply polynomials by one another and understand the formation of terms through products. Real-world applications, like calculating areas and volumes using algebraic expressions, are also discussed.

Key Topics

  • Addition and subtraction of algebraic expressions
  • Multiplication of algebraic expressions
  • Monomials, binomials, and polynomials
  • Distributive law and its applications
  • Real-world applications of algebraic expressions

Learning Objectives

  • Understand and perform addition and subtraction of algebraic expressions.
  • Learn to multiply monomials, binomials, and trinomials.
  • Apply the distributive law in simplifying expressions.
  • Analyze real-world problems involving algebraic expressions for areas and volumes.
  • Differentiate between polynomials based on the number of terms.

Questions in Chapter

Add: ab – bc, bc – ca, ca – ab

Page 94

Subtract 4a – 7ab + 3b + 12 from 12a – 9ab + 5b – 3

Page 95

Carry out the multiplication of these pairs: 4p, q + r

Page 100

Multiply the binomials: (2x + 5) and (4x – 3)

Page 102

Additional Practice Questions

How do you simplify the expression 3x(4x − 5) + 3?

medium

Answer: 3x(4x − 5) + 3 simplifies to 12x² − 15x + 3.

What is the result when 2p(3p + 4) is expanded?

easy

Answer: The result is 6p² + 8p.

Solve for y in the equation 3y(y – 4) + 12 = 0.

hard

Answer: For y = 4, the equation holds true.

Explain how to multiply the expressions (x + 1)(x − 1).

medium

Answer: Using the distributive property, (x + 1)(x − 1) = x² − x + x − 1 = x² − 1.

What is the simplified form of 5x(x + y) + 3(x + y)?

medium

Answer: The simplified form is (5x + 3)(x + y).