The problem asks to subtract the polynomial $(-9m^3 + 9m + 3.4)$ from the polynomial $(7m^3 + 8m^2 - m + 2.3)$. The result should be simplified.

1. Problem Description

The problem asks to subtract the polynomial $(-9m^3 + 9m + 3.4)$ from the polynomial $(7m^3 + 8m^2 - m + 2.3)$. The result should be simplified.

2. Solution Steps

The expression is $(7m^3 + 8m^2 - m + 2.3) - (-9m^3 + 9m + 3.4)$.

First, distribute the negative sign to the second polynomial:

$7m^3 + 8m^2 - m + 2.3 + 9m^3 - 9m - 3.4$

Now, combine like terms:

$(7m^3 + 9m^3) + 8m^2 + (-m - 9m) + (2.3 - 3.4)$

$16m^3 + 8m^2 - 10m - 1.1$

3. Final Answer

$16m^3 + 8m^2 - 10m - 1.1$