Find all solutions of the equation x^2+4x+8=0 and express them in the form a+bi:?

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Find all solutions of the equation x^2+4x+8=0 and express them in the form a+bi:

First input the solution with b < 0 here:
the real number a equals ___________ and the real number b equals _________
Then input the solution with b > 0 here:
the real number a equals __________ and the real number b equals__________

I really don't understand this question which is due soon. Thanks for any help
 
The trick is to be able to factor your first equation, and solve for x.
x^2 + 4x = -8
x^2 + 4x + 4 = -8 + 4
(x+2)^2 = -4
x+2 = +/- sqrt(-4)
x = -2 +/- 2i

The real trick of the problem is "completing the square" where you decide to "add 4" to both sides of the equation.

So, based on the value you found for x above, you can fill in your questionnaire:

First input the solution with b < 0 here:
the real number a equals ___-2_____ and the real number b equals ___-2______
Then input the solution with b > 0 here:
the real number a equals ____-2____ and the real number b equals____2______
 
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