20) \( \begin{array}{l}2 x+3 y=-12 \\ 5 x-3 y=-9\end{array} \)

To solve the system of equations \(2x + 3y = -12\) and \(5x - 3y = -9\), you can use the elimination method. First, add the two equations together to eliminate \(y\): \[ (2x + 3y) + (5x - 3y) = -12 - 9 \\ 7x = -21 \\ x = -3 \] Now, substitute \(x = -3\) into either equation to find \(y\). Using the first equation: \[ 2(-3) + 3y = -12 \\ -6 + 3y = -12 \\ 3y = -6 \\ y = -2 \] The solution to the system of equations is \(x = -3\) and \(y = -2\). Now, if you want to check your solution, simply plug \(x\) and \(y\) back into both original equations. If both equations are satisfied, you've got it right!