Solution - Simplification or other simple results

Reformatting the input :

Changes made to your input should not affect the solution:

(1): "*-6" was replaced by "*(-6)".

Step  1  :

 1.1     6 = 2•3

(6)² = (2•3)² = 2² • 3²

Equation at the end of step  1  :

  ((0 -  (22•32)) +  -30) -  5

Step  2  :

Final result :

  -71