Page 2 - LN 2.1

 Variable: a symbol, usually a letter, that can represent different values

 Equation: Condition given on an expression gives an equation.

Example: 5x + 2 is an expression

But if 5x + 2 = 17 is an equation

CONTENT

(LEARNER’S BOOK – 2.1)
You can write an algebraic expression by using a letter to represent an unknown number.
In the expression 3n + 8 there are two terms.

3n is one term. The other term is 8.

The letter n is called the variable, because it can have different values.
The coefficient of n is 3, because it is the number that multiplies the variable.

The number 8 is called a constant.
Example: Let n represent a mystery number.

You write the number that is 5 more than the mystery number as n + 5 or 5 + n.

You write the number that is three times the mystery number as 3 × n or simply 3n.

SIS/ CAMBRIDGE / LESSON NOTES/2025-26
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