Mathematics Notes for Class 6 Algebra

Algebra

Welcome to the chapter on Algebra for Class 6. In this chapter, you will learn about algebraic expressions, variables, constants, and how to solve simple equations. By the end of this chapter, you will be able to use algebra to solve problems and understand patterns in mathematics!

Introduction

Algebra is a branch of mathematics that uses letters and symbols to represent numbers. These letters are called variables. Algebra helps us solve problems where some values are unknown.

Key Terms in Algebra

Variable: A letter that stands for a number (like x, y, z).
Constant: A fixed number (like 2, 5, 10).
Expression: A combination of variables, constants, and operations (like 2x + 3).
Equation: A statement that two expressions are equal (like x + 5 = 9).

Algebraic Expressions

An algebraic expression can have variables, constants, and operations (addition, subtraction, multiplication, division).

3x + 2
y - 7
5a × 4

Simple Equations

An equation has an equal sign (=). It shows that two sides are the same.

x + 3 = 7
2y = 10

To solve an equation, find the value of the variable that makes the equation true.

x + 3 = 7 → x = 4
2y = 10 → y = 5

Using Algebra in Word Problems

Algebra helps us solve problems where something is unknown. Read the problem, write an equation, and solve for the variable.

Example: Riya has x chocolates. She gets 5 more and now has 12. What is x?
Equation: x + 5 = 12 → x = 7

Fun Activity: Find the Number!

Think of a number, add 4, and tell your friend the answer. Can your friend use algebra to find your number?

Summary

Algebra uses letters to stand for numbers.
Expressions have variables, constants, and operations.
Equations show two sides are equal.
We solve equations to find unknown values.

Practice Questions

Write an algebraic expression for: 5 more than a number x.
Solve: y - 3 = 8
What is the variable in the expression 2a + 7?
If 3z = 15, what is z?
Write an equation for: A number n divided by 2 is 6.

Challenge Yourself

Make your own word problem using algebra.
Solve: 4x + 2 = 18

Did You Know?

Algebra comes from an Arabic word meaning "reunion of broken parts".
Algebra is used in science, engineering, and computer programming!

Glossary

Variable: A letter that stands for a number.
Constant: A fixed number.
Expression: A group of numbers, variables, and operations.
Equation: A statement that two expressions are equal.

Answers to Practice Questions

x + 5
y = 11
a
z = 5
n ÷ 2 = 6

Practice algebra every day to become a math wizard!

Mathematics Class 6 - Algebra Notes