This is a second-order ODE since the highest order derivative is 2 (from

).
It's not linear because it doesn't take the form

and it's not possible to rewrite it as such.
Answer:
4.2
Step-by-step explanation:
took a bullet for the team
Pemdas
Parentheses none
Exponents none
Multiplication 18 multiplied by 2 is 36
Division 36 divided by 4 is 9
Addition none
Subtraction 9 minus 36 is -27
Your answer is -27