To add the complex numbers \( (3 + 4i) + (5 - 6i) \), you can combine the real parts and the imaginary parts separately:
- Real Parts: \( 3 + 5 = 8 \)
- Imaginary Parts: \( 4i - 6i = -2i \)
Putting it all together, we have:
\[ (3 + 4i) + (5 - 6i) = 8 - 2i \]
So the final answer is \( 8 - 2i \).