Answer
$a_{12}=-8,192$
Work Step by Step
RECALL:
The $n^{th}$ term ($a_n$) of a geometric sequence can be found using the formula:
$a_n= a_1 \cdot r^{n-1}$
where
$a_1$ = first term
r = common ratio
Use the formula above and the give values of the first term and the common ratio to obtain:
$a_n=4 \cdot (-2)^{n-1}
\\a_{12}=4 \cdot (-2)^{12-1}
\\a_{12}=4 \cdot (-2)^{11}
\\a_{12}=4 \cdot (-2048)
\\a_{12}=-8,192$
