Solution - Simplification or other simple results

Step  1  :

 1.1     20 = 22•5

(20)² = (2²•5)² = 2⁴ • 5²

Equation at the end of step  1  :

  (372) -  (24•52)

Step  2  :

Equation at the end of step  2  :

  372 -  (24•52)

Step  3  :

Final result :

  969