You might have learnt about representing various **types of numbers** such as **Natural** **numbers,** **Whole** **numbers**, **Integers**, **Rational** **numbers** on the **number** **line**.

**Rational Numbers: **Numbers that can be written in the form of , where **p, q ** and .

The **collection of Rational numbers** is denoted by **Q**. Between any **two rational numbers** there exists **infinitely** **many** **rational** **numbers**.

**Irrational numbers:**Numbers which cannot be expressed in the form of **,** where **p, q **** and**.

The **collection of irrational numbers** is denoted by**.**

**Pythagoras Theorem: **In a **right-angled triangl**e, the **square of the hypotenuse** is equal to **the sum of the squares of the other two sides**.

Using this theorem we can represent the **irrational numbers** on the **number line**.