How do we factorise an expression?

Step 1: Find the highest common factor of the terms in the expression eg. 3x+12. In this expression 3 is the highest common factor of the terms 3x and 12 Step 2: Write the factor outside the brackets eg. 3x+12= 3 (  ) Step 3: Work out what you need to multiply the factor by to get each term in the original expression eg. 3* x = 3x 3*4=12 3x+12 =3 (x  4) Step 4: Write the + or - sign from the original expression inside the brackets eg. 3x + 12 = 3 (x + 4)