CBSE · Class 6-12

Class 7 · Ganita Prakash

Unit 4 · Class 7Ganita Prakash

Expressions using Letter-Numbers

Introduction to algebraic expressions and variables.

Lessons

3 concepts

1
Building Expressions
'Add 5 to $x$ ' becomes $x + 5$ . 'Twice a number decreased by 3' becomes $2x - 3$ . Practice translating English into algebra.
2
Terms and Coefficients
In $3x + 5$ , $3$ is the coefficient of $x$ and $5$ is a constant term. Term separators are $+$ and $-$ .
3
Combining Like Terms
$4x + 2x = 6x$ . But $3x + 5y$ cannot combine — different variables. $2x^2 + 3x^2 = 5x^2$ combines because both have $x^2$ .

Skills to practise

Skill · medium

Expressions using Letter-Numbers — Practice