Algebra

• A variable is something that does not have a fixed value. The value of a variable varies.
• Variables are represented by English letters such as x, y, z, a, b, c etc.
• A combination of variables, numbers and operators (+, –, × and ÷) is known as expression.

• Using different operations on variables and numbers, expressions such as , can be formed.

Example: 

Meena’s age is 4 years less than 7 times the age of Ravi. Express it using variables. 

Solution:

Let the age of Ravi be x years.

7 times the age of Ravi can be expressed as 7x.

4 years less than…