#### Answer

$-5-12i$

#### Work Step by Step

Using $(a+b)^2=a^2+2ab+b^2$ or the square of a binomial, the given expression, $
(-2+3i)^2
,$ simplifies to
\begin{array}{l}\require{cancel}
(-2)^2+2(-2)(3i)+(3i)^2
\\\\=
4-12i+9i^2
\\\\=
4-12i+9(-1)
\\\\=
4-12i-9
\\\\=
-5-12i
.\end{array}