Having problems with the FOIL for the problem below

(5x^8-5)(x^9-4).
My answer is 5x^17-20x-5^9-20. please let me know if this is correct. if not correct can you show me what i need to do?

It would help if you proofread your questions before you post them. A negative times a negative = positive.

5x^17 - 20x^8 - 5x^9 + 20