Find x and y

Given:

\[ \begin{bmatrix} x+3 & 4 \\ y-4 & x+y \end{bmatrix} = \begin{bmatrix} 5 & 4 \\ 3 & 9 \end{bmatrix} \]

Step 1: Compare Corresponding Elements

\[ x + 3 = 5 \Rightarrow x = 2 \]

\[ y – 4 = 3 \Rightarrow y = 7 \]

\[ x + y = 9 \Rightarrow 2 + 7 = 9 \quad (\text{verified}) \]

Final Answer:

\[ x = 2,\quad y = 7 \]