The roots (values of X) of the following quadratic equation

Question

x^2 + 2x + 4 = 0

Answer 1

Given equation x^2 + 2x + 4 = 0

Compare above equation with  a x^2 + b x + c = 0.

a = 1, b = 2, c = 4.

x = [- b ± √(b ^2 - 4ac]/2a

x = [- 2 ± √(2^2 - 4(1)(4))] / 2(1)

x = [- 2 ± √(4 - 16)] / 2

x = [- 2 ± √(-12)] / 2

x = [- 2 ± √(-3)(4)] / 2

x = [- 2 ± i2√3] / 2

x = - 1 ± i√3

x = - 1 + i√3  and  x = - 1 - i√3.

Answer :

Solution is 

x = - 1 + i√3  and  x = - 1 - i√3.