Final answer:
The expression √(-245) - 245 cannot be simplified further or expressed in simplest radical form since the square root of -245 is not defined in the real number system.
Step-by-step explanation:
To write the expression √(-245) - 245 in simplest radical form, we need to simplify the square root of -245 first. Since -245 is a negative number, the square root of -245 is not a real number. Therefore, the expression √(-245) is not defined in the real number system. As a result, we cannot simplify the given expression further or express it in simplest radical form.