Solution - Simplification or other simple results

Step  1  :

 1.1     42 = 2•3•7

(42)² = (2•3•7)² = 2² • 3² • 7²

Equation at the end of step  1  :

  (582) -  (22•32•72)

Step  2  :

 2.1     58 = 2•29

(58)² = (2•29)² = 2² • 29²

Equation at the end of step  2  :

  (22•292) -  (22•32•72)

Step  3  :

Final result :

  1600