Answer :
This is an equation in x. We need to use distribution property to simplify and use algebra to solve for x.
Process shown below.
[tex]\begin{gathered} -3\mleft[x+5\mright]+1=7\mleft[x+5\mright]+8 \\ -3x-15+1=7x+35+8 \\ -3x-14=7x+43 \\ -14-43=7x+3x \\ -57=10x \\ x=-\frac{57}{10} \\ x=-5.7 \end{gathered}[/tex]