Question #b9b3d

1 Answer
Oct 30, 2016

p=-1/2+-i

Explanation:

Standard form:" "y=ax^2+bx+c" " =>" " x=(-b+-sqrt(b^2-4ac))/(2a)

In this " "a=1"; "b=1"; "c=4 giving

p=(-1+-sqrt(1^2-4(1)(4)))/(2(1))

p=-1/2+-sqrt(-16)/2

Which is the same as:

p=-1/2+-sqrt(4^2xx(-1))/2

p=-1/2+-(cancel(2)sqrt(-1))/(cancel(2))

But sqrt(-1) = i

p=-1/2+-i