calculate the subtraction (8.5-1.8i) - (-1.3+2.7i). provide the answer in the form of a+bi.
To subtract complex numbers, subtract the real parts and the imaginary parts separately.
Given (8.5 - 1.8i) - (-1.3 + 2.7i):
Subtract the real parts: 8.5 - (-1.3) = 8.5 + 1.3 = 9.8
Subtract the imaginary parts: -1.8i - 2.7i = -4.5i
Therefore, (8.5 - 1.8i) - (-1.3 + 2.7i) = 9.8 - 4.5i
The answer is 9.8 - 4.5i.