Answer:
-x²+9x+13
Step-by-step explanation:
if your question is (-6x²+5)-(-5x²-9x-8)
-(-a-b)=(a+b)
=-6x²+5+5x²+9x+8
=-6x²+5x²+9x+5+8
=-6x²+5x²+9x+13
Then the answer is -x²+9x+13
