We have to prove x = -16/3.
The steps are:
[tex]1)3(x+5)=-1\longrightarrow\text{Reason: Given}[/tex][tex]2)3x+15=-1\longrightarrow\text{Reason: Distributive property}[/tex][tex]3)3x=-16\longrightarrow\text{ Reason: substracting 15 from both sides}[/tex][tex]4)x=-\frac{16}{3}\longrightarrow\text{ Reason: divide both sides of the equation by 3}[/tex]