Answer
$-\frac{3}{4}$
Work Step by Step
According to the negative exponent rule, $a^{-n}=\frac{1}{a^{n}}$.
Therefore, $-2^{-1}-4^{-1}=-(2^{-1}+4^{-1})=-(\frac{1}{2}+\frac{1}{4})=-(\frac{1\times2}{2\times2}+\frac{1}{4})=-(\frac{2+1}{4})=-(\frac{3}{4})=-\frac{3}{4}$.
