Question

Which of the following is a solution of x2 + 4x + 6?
−2 + i times the square root of 2
2 + i times the square root of 2
−2 + three i times the square root of 2
−2 + three i times the square root of 2

Answer 1

you have a choice
you can use the quadratic formula or you can complete the square
you pick

Answer 2

actually there is a third choice, namely to cheat

Answer 3

how do i do that, any of it ?

Answer 4

do you know the quadratic formula?

Answer 5

i need a refresher.

Answer 6

the solutions to
\[ax^2+bx+c=0\] are
\[x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}\]
in your case \(a=1,b=4,c=6\) but also in your case completing the square is easier

Answer 7

lets solve
\[x^2+4x+6=0\] by completing the square
ready?

Answer 8

sorry i was working it out xD

Answer 9

ok take your time

Answer 10

so far I got