We should start by looking for the highest common factor of the 2 numbers involved in the equation (3&12)If you cannot do this immediately in your head, create a factor tree or list the factors3: 312: 2, 3, 4, 6, 12The highest common factor is 3, so we put 3 outside the bracket:3(Now, what do we need to multiply 3 by to get 3x?3(xNow, what do we need to multiply 3 by to get 12?3(x+4)