Answer:
[tex]-12x^2-5x-8[/tex]
Step-by-step explanation:
Model the given expression such that it can be solved,
[tex](-9x^2+3x-8)-(3x^2+8x)[/tex]
Distribute the negative sign outside the parenthesis,
[tex]-9x^2+3x-8-3x^2-8x[/tex]
Combine like terms,
[tex]-12x^2-5x-8[/tex]
