Answer:  
                   
                    To factorise a number means to write it as a product of its 
                    factors. 
                   
                    For example, 10 can be written as 1 x 10 or 2 x 5 while 12 
                    can be written as 1 x 12 or 2 x 6 or 3 x 4. 
                   
                    In the same way an algebraic expression can be factorised 
                    by writing it as a product of its factors. 
                   
                    For example, 2x + 2y can be factorised as 2 x (x + y), usually 
                    written as 2(x + y). Another example, the number 15 factors 
                    into primes as 3 × 5, and the polynomial x2 
                    - 4 factors as (x - 2)(x + 2).  
                  In 
                    all cases, a product of simpler objects is obtained. The aim 
                    of factoring is usually to reduce something to basic building 
                    blocks, such as numbers to prime numbers.. 
           
             |