Constant and variables

ALGEBRA

Lesson: Variables and Constants in Algebra

Objective:

By the end of this lesson, you'll understand:

 What variables are.

 What constants are.

 How variables and constants are used in algebraic expressions.

What are Variables?

A variable is a symbol (usually a letter) that represents an unknown value or
a value that can change. It is often used in algebra to represent numbers
that can vary or be replaced by different values.

 Common Variables: xxx, yyy, zzz, aaa, bbb, etc.

Example of a Variable:

 x+5=10x + 5 = 10x+5=10

In this equation, xxx is the variable. It can be any number, and we need to
find out what value of xxx makes the equation true.

Why Do We Use Variables?

 Flexibility: Variables allow us to work with unknowns or quantities
that can change.

 Generalization: Variables help express general relationships or
patterns that hold true for many different numbers.

What are Constants?

A constant is a fixed value that does not change. It is a number that
remains the same no matter what.

 Common Constants: 3, -7, 10, π\piπ, 0, etc.

Example of a Constant:

 3x+5=153x + 5 = 153x+5=15

In this equation:

 333 is a constant (it’s a fixed number).