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GCSE Maths Exercises you can do!
LikeThis is not just aimed at GCSE students. It is for anyone wishing to improve their maths- or you could just try these for fun!
So let's start off with something easy.
1) In maths a letter can be used, which is called a variable. This variable can be the letter or "a" or "x" or any other letter. This letter can mean any number possible. We can give it a value. So where we say "x" is equal to 1 , Now "x" is 1.
Here you are given a triangle which has sides of which the lengths are unknown and given to you with variables for you to work out.
So here it says the "perimeter" of the triangle is equal to 47cm. This means the lengths of every side added up, gives you 47cm.
To work this out we add the values 2x+3 and 3x-5 and 2x. When we have a number next to a letter, this means we multiply the letter by that number. So the perimeter equals 2 groups of x + 3 groups of x + 2 groups of x + 3 - 5. Therefore, the perimeter equals 7 groups of x - 2
The way we write this is: Perimeter= 2x+3 + 3x-5 + 2x = 7x-2
Now we have the perimeter: 7x-2. And we know that the perimeter is 47cm (these are different ways of saying the perimeter).To find the value of X, we make 7x-2 = 47cm. Because they are both meanings of the perimeter for this triangle. 7x-2 = 47
So we use a rule of algebra. We want to separate the letter x from the numbers. And the rule is if you add, minus, multiply or divide, you have to do it for BOTH sides of the equal sign or your answer will be wrong.
- 7x-2 +2 = 47 +2 Add 2 on both sides of the equation
- 7x = 49 This gives you this.
- 7x divided by 7 = 49 divided by 7 Next, divide both sides by 7
- x = 49 divided by 7. 49/7 = 7. This gives us 7.
- x = 7 7cm is our answer.
THE ANSWER IS: a) 7cm
Well Done! Maths isn't really that hard, just a series of easy steps which take 2 things: time and practise.