13. Given variables $x, y$ satisfy the constraint conditions
$$
\left\{\begin{array}{l}
x-y+2 \leqslant 0, \\
x \geqslant 1, \\
x+y-7 \leqslant 0 .
\end{array}\right.
$$

Then the range of $\frac{y}{x}$ is $\qquad$
13. $\left[\frac{9}{5}, 6\right]$.
According to the problem, the intersection points of the desired region are
$$
\left(\frac{5}{2}, \frac{9}{2}\right),(1,6)
$$