The equation visible in the image is:

$3 - 7i + 5i - 1 - 4i$

We need to simplify it and write the answer in the form $a + bi$, where $a$ is the real part and $b$ is the imaginary part.

Simplification:

1. Combine the real parts: $3 - 1 = 2$
2. Combine the imaginary parts: $-7i + 5i - 4i = -6i$

Thus, the simplified form is:

$2 - 6i$

So the answer is $2 - 6i$.

Would you like more details or have any other questions?

Here are some related questions to practice:

1. Simplify $5 - 3i + 4i - 2$.
2. Express $4 + 7i - 2 + 5i$ in standard form.
3. What is the result of $(6 + 2i) + (3 - 5i)$?
4. Simplify $2 + 4i - 1 - 3i + 5i$.
5. What is the real and imaginary part of $7 - 3i + 6 - 8i$?

Tip: When simplifying complex numbers, always group real and imaginary parts separately for easier handling.