Simplify the expression below as much as possible. (9+81) + (4 - 7i) - (9-6i) O A. 4-5i O B. 4+9i O c. 4 + 21i O D. 4 + 7i​

Respuesta :

9514 1404 393

Answer:

  D.  4 +7i

Step-by-step explanation:

Combine like terms.

  (9 +8i) +(4 -7i) -(9 -6i) = (9 +4 -9) +(8 -7 -(-6))i = 4+7i