Answer:
-117
Step-by-step explanation:
Hello!
If f(x)=2x^2-x, then f(-4) = 2(-4)^2 - (-4) = 2(16) + 4 = 36, and
f(9) = 2(9)^2 - 9 = 153
Therefore, f(-4) - f(9) = 36 - 153 = -117
