To solve for $f(4)$ given the function $f(x) = -x + 2$, we simply substitute $x = 4$ into the function:

$f(4) = -(4) + 2$

Calculating this:

$f(4) = -4 + 2 = -2$

So, the answer is: $f(4) = -2$

Would you like a further breakdown or explanation of this solution? Here are some related questions for further exploration:

1. How would the solution change if the function was $f(x) = -2x + 2$?
2. What is $f(x)$ if $x = -4$?
3. What is the inverse of the function $f(x) = -x + 2$?
4. How would we find $f(4)$ if $f(x) = x^2 - x + 1$?
5. What would $f(x) = -x + 2$ look like if graphed on a coordinate plane?

Tip: When evaluating functions, substitute the input value carefully and follow the order of operations to avoid mistakes.