Question

Subtract the complex numbers: (-2 + 12i) - (-1 - 9i)

Answer 1

Answer:

B. -3 + 3i

Step-by-step explanation:

Using the foil method:

-2 - 1 = -3

12i - 9i = 3i

= -3 + 3i

Answer 2

9514 1404 393

Answer:

  C)  -1 +21i

Step-by-step explanation:

For many purposes, "i" can be treated as though it is a variable. Collect terms in the usual way.

  (-2 +12i) -(-1 -9i) . . . . given

  = -2 +12i +1 +9i . . . . use the distributive property to eliminate parentheses

  = (-2+1) +(12i +9i) . . . group like terms

  = -1 +21i