To solve $f(x) - g(x)$, where $f(x) = 2x + 5$ and $g(x) = 3x + 4$, we proceed as follows:

1. Substitute the given functions into the expression $f(x) - g(x)$:

$f(x) - g(x) = (2x + 5) - (3x + 4)$

2. Distribute the negative sign across the terms in $g(x)$:

$f(x) - g(x) = 2x + 5 - 3x - 4$

3. Combine like terms:

$f(x) - g(x) = (2x - 3x) + (5 - 4)$

$f(x) - g(x) = -x + 1$

So, the solution is:

$f(x) - g(x) = -x + 1$

Would you like more details or have any other questions? Here are some related questions:

1. What happens when $f(x) = g(x)$?
2. How do you find $f(x) + g(x)$ for the given functions?
3. How do you find the roots of $f(x) - g(x) = 0$?
4. What is the value of $f(x) - g(x)$ when $x = 2$?
5. How do you find the intersection points of $f(x)$ and $g(x)$?

Tip: When subtracting functions, always remember to distribute the negative sign to each term in the second function before combining like terms.