Question

Which of the following is a solution of x2 + 4x = −8

A. x = −2 − 2i
B. x = 2 + 2i
C. x = −4 + 4i
D. x = 4 − 4i

Answer 1

x=-2-2i and -2+2i

Explanation:

took test

Answer 2

add 8 both sides
x²+4x+8=0
we can't factor this
we use quadratic formula
for ax²+bx+c=0
x=
`(-b+/- √(b^2-4ac) )/(2a)`
so
a=1
b=4
c=8

x=
`(-4+/- √(4^2-4(1)(8)) )/(2(1))`
x=
`(-4+/- √(-16) )/(2)`
x=
`(-4+/- 4i )/(2)`
x=-2+/-2i

x=-2-2i and -2+2i


A is answer