EDEXCEL GCSE FOUNDATION MATHS - What are Square Numbers and Square Roots

EDEXCEL GCSE FOUNDATION MATHS: Square Numbers and Square Roots

What is a Square Number?

A square number is the result of multiplying a whole number by itself.

• For example, 9 is a square number because it's the result of 3 x 3 (3 squared).

How to Find Square Numbers

To find the square of a number, simply multiply the number by itself. You can use the following symbol to represent squaring a number:
^2*

Examples:

• 2^2 = 2 x 2 = 4
• 5^2 = 5 x 5 = 25
• 10^2 = 10 x 10 = 100

What is a Square Root?

The square root of a number is the number that, when multiplied by itself, equals the original number.

• For example, the square root of 9 is 3 because 3 x 3 = 9.

How to Find Square Roots

You can find the square root of a number using a calculator, or by using the following symbol:

• ?

Examples:

• ?4 = 2
• ?25 = 5
• ?100 = 10

Key Things to Remember:

• The square root of a number is always a positive number.
• Not all numbers have whole number square roots.

Practice:

1. Find the squares of the following numbers:

   • 4
   • 7
   • 12

2. Find the square roots of the following numbers:

   • 16
   • 64
   • 144

Answers:

1. • 16, 49, 144
2. • 4, 8, 12