Solution - Simplification or other simple results

Reformatting the input :

Changes made to your input should not affect the solution:

 (1): "a1"   was replaced by   "a^1". 

Step  1  :

Equation at the end of step  1  :

  5a18 -  4a

Step  2  :

Step  3  :

Pulling out like terms :

 3.1     Pull out like factors :

   5a¹⁸ - 4a  =   a • (5a¹⁷ - 4) 

Final result :

  a • (5a17 - 4)