Answer:
-10x^6+5x^5+15x^4-10x^3-6x^2.
Step.by-step explanation:
5x^5+4x^2-2x^6+6x^4 - (10x^2+10x^3+8x^6-9x^4).
First distribute the negative over the parentheses:
=5x^5+4x^2-2x^6+6x^4 - 10x^2-10x^3-8x^6+9x^4
Now bring like terms together:
= -2x^6-8x^6+5x^5+6x^4+9x^4-10x^3+4x^2-10x^2
= -10x^6+5x^5+ 15x^4-10x^3-6x^2.