21 because 9+10 is actually 21
Answer:
Step-by-step explanation:
8(1 + 2i) - (7 - 3i) = 8*1 + 8*2i + 7*(-1) - 3i*(-1)
= 8 + 16i -7 + 3i
= 8 - 7 + 16i + 3i
= 1 + 19i
Daniel forgot to multiply 2i by 8
So there is a real and imaginary axis
the midopint is just the average of them
average between the reals is (5-3)/2=2/2=1
average between imaginaries is (18i+2i)/2=20i/2=10i
center is 1+10i
