Answer
$-9-38i$
Work Step by Step
Note: the standard form of a complex number is $a+bi$ where $i = \sqrt -1$ and $a$ and $b$ are real numbers.
Note: $i^{2} = \sqrt -1\sqrt -1 = -1$
$(3-4i)(5-6i)$
First, expand out the complex number:
$15-18i-20i+24i^{2}$
As seen in the note above, $i^{2} = -1$, so substitute in $-1$.
$15-18i-20i+24(-1)$
$15-18i-20i-24$
Combine like terms, to express the complex number in standard form:
$-9-38i$
