Solve using substitution. \[ \begin{array}{l}x+4 y=-17 \\ x-9 y=9\end{array} \] \( (\square, \square) \)

Let's solve the system of equations using substitution. Start with the first equation: 1. From \( x + 4y = -17 \), we can express \( x \) in terms of \( y \): \[ x = -17 - 4y \] 2. Now, substitute this expression for \( x \) into the second equation \( x - 9y = 9 \): \[ (-17 - 4y) - 9y = 9 \] 3. Combine like terms: \[ -17 - 13y = 9 \] 4. Add 17 to both sides: \[ -13y = 26 \] 5. Divide by -13: \[ y = -2 \] 6. Now, substitute \( y = -2 \) back into the expression for \( x \): \[ x = -17 - 4(-2) = -17 + 8 = -9 \] So, the solution to the system of equations is \( (-9, -2) \). The final result is: \( (-9, -2) \)