Question

Which of the following equations has only one solution?
x2 + 4x + 4 = 0
x2 + x = 0
x2 - 1 = 0
and why

Answer 1

They all do....

x2+4x+4=0 >> 6x = -4 >> x =-4/6

x2+x = 0 >> 3x =0 >> x =0

x2-1=0 >> 2x = 1 >> x =1/2

Answer 2

when he says x2 he means x squared.

and it has to be the first one, you can easily tell the other two have to solutions.
But to make sure:

\[x = { -4 \pm \sqrt{16-16} \over 2 } = -2\]

So that is indeed the one.

Answer 3

im a girl :P