In both coefficient of x^3 is 1. 1st cubic ends in +3 and 2nd in +2. So any common factors can only be (x+1) or (x-1) giving roots -1 or 1

If x=1 is a common root 1+k+1+3=0 and 1+2+k+2=0 Both give k=-5

If x=-1 is a common root -1+k-1+3=0 and -1+2-k+2=0 These dont give the same k

So answer is k=-5 giving a common root of x=1