# How do you simplify (-2)(15i)(-3i)?

$- 90$
Since ${i}^{2} = - 1$, we may simplify this as follows
$\left(- 2\right) \left(15 i\right) \left(- 3 i\right) = \left(- 2\right) \left(15\right) \left(- 3\right) \left(- 1\right)$
$= - 90$