Solving quadratic equations by factorising:
To solve a quadratic equation, the first step is to write it in the form ax2 + bx + c = 0

Example:

Solve the equation x2 - 9x + 20 = 0

Now find the value x so that when these brackets are multiplied together the answer is 0

This means either (x - 4) = 0 or (x - 5) = 0

So x = 4 or x = 5

Using the quadratic formula:
Here a, b and c are numbers that vary for different equations. So if the equation was
2x(2) + 7x + 11 = 0
then a = 2, b = 7 and c = 11