Question

what are the solutions of x^2+4x+5=0

Answer 1

x^2+4 x+5 = 0
Subtract 5 from both sides:
x^2+4 x = -5
Add 4 to both sides:
x^2+4 x+4 = -1
Factor the left hand side:
(x+2)^2 = -1
Take the square root of both sides:
abs(x+2) = i
Eliminate the absolute value:
x+2 = -i or x+2 = i
Subtract 2 from both sides:
x = -2-i or x+2 = i
Subtract 2 from both sides:
x = -2-i or x = -2+i

Answer 2

\[x=\frac{-b+/-\sqrt{b^2-4ac}}{2a}\]

Answer 3

\[x=\frac{-4+/-\sqrt{4^2-4(1)(5)}}{2}\]

Answer 4

\[x=\frac{-4+/-4i}{2}=-2+/-2i\]