Question

Solve the quadratic equation x^2 - 4x + 57 = -5 by completing the square.
A.x=1±i√50
B.x=2±√58
C.x=2±i√58
Dx=2±√62

Answer 1

\[ x^2 - 4x + 57 = -5\Rightarrow x^2 - 4x +4-4+ 57 = -5\Rightarrow\\
\Rightarrow (x - 2)^2-4 + 57 = -5\Rightarrow (x-2)^2=-58\]

Answer 2

\[x-2=\pm i\sqrt{58}\Rightarrow x=2\pm i\sqrt{58}\]

Answer 3

@John_ES is correct. Well Done!

Answer 4

thank you !