Answer
$$x=-1.585$$
Work Step by Step
$$3-2^{-x}=0$$
$$2^{-x}=3$$
- Draw the graph of the function $y= 2^{-x}$
- Draw the graph of the function $y=3$
- Trace the point of intersection of the 2 graphs, the $x$ value of which is the answer to the given equation.
Thus, from the graph, as the point of intersection is $(-1.585,3)$, we conclude that $$x=-1.585$$