Mathematics · Class 6
Algebra
Variables, expressions, and simple equations using the balance method.
4 sections15–25 min read6 MCQs · 2 examples
Chapter Overview
Algebra introduces variables (letters) to represent unknown numbers. You learn expressions, equations, and the method of solving simple equations using balance — foundation for all higher mathematics.
Variables and Expressions
- Variable: letter like x, y that can take different values
- Expression: combination of terms (e.g. 3x + 5)
- Equation: equality with variable (e.g. x + 3 = 7)
Forming Expressions
- '5 more than x' → x + 5
- '3 times y' → 3y
- '10 less than a number n' → n − 10
Solving Equations
Keep equation balanced: do the same operation on both sides. To solve x + 4 = 9, subtract 4 from both sides to get x = 5.
Solved Examples
Step-by-step solutions — read each step before checking the final answer.
Example 1: Form Expression
Raju has x marbles. He gets 8 more. Write total marbles.
- 1Start with x
- 2Add 8 more
Answer
x + 8 marbles
Example 2: Solve Equation
Solve y − 5 = 12.
- 1Add 5 to both sides
- 2y = 12 + 5
Answer
y = 17
Key Points to Remember
- ✓ LHS = RHS in any equation
- ✓ Transposition: move term to other side with sign change
- ✓ Check solution by substitution
Exam Tips
- • Show balancing steps clearly
- • Verify answer by putting back in original equation
Practice MCQs — Algebra
Test your understanding with topic-wise multiple choice questions. Explanations appear after each answer.
Question 1 of 6Score: 0/0
If x = 4, value of 3x + 2 is: