3.28=-0.41(k+-5)
Distribute your -0.41 to both k and -5.
It will look like this: 3.28=-0.41(k) + -0.41(-5)
You now have 3.28= -.041k+2.05, and have to subtract 2.05 from both sides to try and get k alone.
So, 1.23=-0.41k, now you divide both sides by -.041, because you cannot have a negative x as an answer.
Your answer will be k= -3