Answer:
4 or -625x^4 (Just in case I misunderstood)
Step-by-step explanation:
The degree is always the power of something. Since -5x has a power of 4, its degree is 4.
Just in case I misunderstood the question, I will solve it another way that I think you meant. (-5x)^4 is -5^4 times x^4.
-625 times x^4 is -625x^4.
