1. The problem involves understanding why the term $(-k+2)$ appears in step 4 of a previous solution. 2. Typically, $(-k+2)$ arises from rearranging or factoring expressions involving $k$ and constants. 3. For example, if you start with an expression like $2 - k$, rewriting it as $-k + 2$ is just changing the order of terms, which is allowed because addition is commutative. 4. This rearrangement helps in factoring or simplifying expressions, especially when grouping terms or factoring out negatives. 5. So, $(-k+2)$ exists because it is equivalent to $(2 - k)$, just written in a form that might be more convenient for the next steps in the solution. 6. This is a common algebraic manipulation to make further steps clearer or easier to perform.