[tex]\bf n^{th}\textit{ term of a geometric sequence}\\\\
t_n=t_1\cdot r^{n-1}\qquad
\begin{cases}
n=n^{th}\ term\\
t_1=\textit{first term's value}\\
r=\textit{common ratio}\\
----------\\
n=6\\
t_1=5\\
r=-\frac{1}{2}\\
\end{cases}\implies t_6=5\left(-\frac{1}{2} \right)^{6-1}[/tex]
