4) $n^2 + 4n - 12$

We need two numbers that multiply to -12 and add up to 4. The numbers are 6 and -2 since $6\times(-2)= - 12$ and $6+( - 2)=4$.

Using the numbers from Step 1, we can factor $n^{2}+4n - 12$ as $(n + 6)(n-2)$.

$(n + 6)(n - 2)$