[tex](4k+5)(k+1)=0[/tex][tex](4k)(k)+(4k)(1)+(5)(k)+(5)(1)=0[/tex][tex]4k^2+4k+5k+5=0[/tex][tex]4k^2+9k+5=0[/tex]
then applying the quadratic formula
[tex]k=\frac{-9\pm\sqrt[]{81-(4)(4)(5)}}{2(4)}=\frac{-9\pm1}{8}[/tex]
then the solutions of the equation will be K=-5/4 and K=-1