Question

which segment is opposite to $\angle x$?
right triangle with right angle at q, vertices x, q, z
answer
$\overline{xq}$ $\overline{xz}$ $\overline{qz}$

Explanation:

In a triangle, the segment opposite an angle is the side that does not form the angle. For $\angle X$, the sides forming the angle are $\overline{XQ}$ and $\overline{XZ}$, so the remaining side is opposite.

Answer:

$\overline{QZ}$