To simplify the expression [tex]\((8 + 5i) + (10 + 6i) - (3 + 6i)\)[/tex], we can follow these step-by-step instructions:
1. Combine the real parts of the complex numbers:
- The real parts of the complex numbers are [tex]\(8\)[/tex], [tex]\(10\)[/tex], and [tex]\(3\)[/tex].
- Add and subtract the real parts:
[tex]\[
8 + 10 - 3 = 15
\][/tex]
2. Combine the imaginary parts of the complex numbers:
- The imaginary parts of the complex numbers are [tex]\(5i\)[/tex], [tex]\(6i\)[/tex], and [tex]\(6i\)[/tex].
- Add and subtract the imaginary parts:
[tex]\[
5i + 6i - 6i = 5i
\][/tex]
3. Combine the results from the real and imaginary parts:
- After combining, we get:
[tex]\[
15 + 5i
\][/tex]
Thus, the simplified expression is [tex]\(15 + 5i\)[/tex].
The correct answer is:
[tex]\[ \boxed{A. \; 15 + 5i} \][/tex]
