Answer:
12 - 4i
Explanation:
Additive inverses undo complex numbers.
Additive Inverses
An additive inverse is a number that when added to another equals zero. For example, -2 and 2 are additive inverses. This is because -2 + 2 = 0. This same idea applies to imaginary numbers and complex numbers. Additive inverses are also known as opposite. To return to the first example, -2 and 2 could also be called opposites.
Finding the Additive Inverse
In order to find the additive inverse, all you need to do to is flip the sign of the numbers. If a number is positive, then make it negative, and vice versa. In the complex number -12 + 4i, -12 is negative and 4i is positive. So, we need to flip their signs.
We can check our work by adding them together and seeing if the sum is 0.
- (-12 + 4i) + (12 - 4i) = 0
So, 12 - 4i is the additive inverse of -12 + 4i.