Search over 10,000 free study notes

We can solve simultaneous equations in two different ways. We can either eliminate one of the unknowns or use substitution. It is about finding which method you are most comfortable with and practicing th...

This is a quick derivation of the quadratic formula for an GCSE Maths students looking to stretch themselves a little and go for that A*!

If we have a general quadratic equation:

It is important to remember this is an estimate, so we can simplify the numbers by saying they get 20% off and the drill costs £90. (1)

10% off would be £9, so 20% off is £18. (1)<...

Step 1 - Identify the difference between the required form of the answer and the expression to be simplified: 

It can be...

(7+√5)/(√5-1) 

In this example we are given (√5-1) as our denominator, and we want to simplify this complex fraction into the form a + b√5. 

In order to do this our first st...