ANSWER:
m + n = -17, m - 9 = n
-4, -13
STEP-BY-STEP EXPLANATION:
According to the statement, we can establish the following system of equations:
[tex]\begin{gathered} m+n=-17 \\ \: m-9=n \\ \\ m+n=-17,m-9=n \end{gathered}[/tex]We substitute the second equation in the first and solve:
[tex]\begin{gathered} m+m-9=-17 \\ 2m=-17+9 \\ m=\frac{-8}{2} \\ m=-4 \\ \\ \text{ Now, for n, replacing the value of m:} \\ n=-4-9 \\ n=-13 \end{gathered}[/tex]Therefore, the numbers are -4 and -13