New GCSE Maths Revision and Learning Blog
Expanding out Brackets - Key Information to Remember
The best way to solve an equation with a set of brackets is by expanding the brackets out. Expanding out brackets is a very important part of the GCSE maths syllabus and will be a skill you’ll have to be able to use in your examinations.
We’ll go through an example step-by-step to help you understand the method we use and revise how to expand a set of brackets out in an equation.
Example:
5(3c - 2) = 25
In order to solve this equation we must find what c is, and in order to do this we must expand out the brackets in the equation.
Firstly, 5 must be timesed by what is inside the brackets
5 x 3c - 2 x 5 = 25
15c - 10 = 25
Then we get rid of -15 by adding 15 to both sides
15c = 35
NB: The method used for solving equations using this method is closely linked to how we solve equations using the balance method. Check out our balance method song and blog if you haven’t already!
Now we must get the c on it’s own by dividing 10 from both sides
C = 35/15
C = 7/3
If you have time, you can check if your answer is correct by inputting your answer into the equation
5(3(7/3) - 2) = 25
5(7 - 2) = 25
5 x 5 = 25
Correct!
Expanding out brackets is easy when you follow our learning and revision tools. Why not check out our song: Expanding out Brackets too! This topic is very important and is something you should know back-to-front before going into your GCSE Maths exam.
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