Answer:
a = 1 ± 3i
Step-by-step explanation:
Rearranging, you have ...
(a^2 -2a +1) +9 = 0
(a -1)^2 = -9 . . . . . . . . subtract 9, write as a square
a -1 = ±3i . . . . . . . . . . take the square root
a = 1 ±3i . . . . . . . . . . . add 1
