The equation to solve is:
[tex]\frac{3}{5t}+7=-8[/tex]We take "7" to the right hand side:
[tex]\begin{gathered} \frac{3}{5t}+7=-8 \\ \frac{3}{5t}=-8-7 \\ \frac{3}{5t}=-15 \end{gathered}[/tex]Now, we cross multiply:
[tex]\begin{gathered} 3=5t\times-15 \\ 3=-75t \end{gathered}[/tex]Now we divide by -75 to solve for t:
[tex]\begin{gathered} 3=-75t \\ t=-\frac{3}{75} \end{gathered}[/tex]