Simplify the given expression below: (4 + 2i) - (1 - 7i)

5 - 5i 5 + 9i 3 + 9i 3 - 5i

The best way to think of complex numbers is through x and y coordinates, if a number is just on its own (real) think of it as the x ordinate. Conversely if the number is say 2i (imaginary), just think of it as the y=2.

So 4+2i - (1-7i) = 4+2i-1+7i = (4-1) + i (2+7) = 3 + 9i

That can be though of as (3,9). A complex number is just two separate real numbers, a real part and an imaginary part.