How to factorise

For example: 5x +25

In order to factorise we need to find a common factor for both '5x' and '25'. This factor gets taken outside of the brackets.

For this example the common factor is 5. Because you can divide both '5x' and '25' by 5 to get whole numbers.

Now we divide '5x' and '25' by the common factor (5) to give us the numbers in brackets
5x ÷ 5 = x
25 ÷ 5 = 5

Therefore our factorisation becomes; 5(x + 5)
The sign (i.e. + - x or ÷) is the same in brackets as it is in the original equation

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