Answer:
3x2+5x−6−x2+3x+9
=3x2+5x+−6+−x2+3x+9
Combine Like Terms:
=(3x2+−x2)+(5x+3x)+(−6+9)
=2x2+8x+3
Answer is: =2x2+8x+3
Step-by-step explanation:
