SOLUTION: x^2+5x+8=0 solve in complex number system

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Question 897438: x^2+5x+8=0 solve in complex number system
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B5x%2B8=0
Complete the square.
x%5E2%2B5x%2B%285%2F2%29%5E2%2B8=%285%2F2%29%5E2
%28x%2B5%2F2%29%5E2%2B8=25%2F4
%28x%2B5%2F2%29%5E2=25%2F4-32%2F4
%28x%2B5%2F2%29%5E2=-7%2F4
x%2B5%2F2=0+%2B-+%28sqrt%287%29%2F2%29i
x=-%285%2F2%29+%2B-+%28sqrt%287%29%2F2%29i