k + (-4.1) is the exact same as saying k- 4.1, so what you have to do now is put the -4.1 in the opposite side, but with opposite sign too (+)
so k= -9.7 + 4.1
so in order to answer it you have to deduct the number with the lowest value taking in count both as positive and the sign will be the one from the highest value taking both as positive
9.7
-4.1
____
5.6
so 9.7 had a negative sign so the answer to your question is
k = -5.6
i hope i helped you