Question

Solve the quadratic equation by completing the square: z² + 16z+39= - 81

Give the equation after completing the square, but before taking the square root. Your answer should look
like: (z-a)² = b
The equation is:
Give all solutions to the equation, including any non-real solutions. The solutions are: z =

Answer 1

`z^2 + 16z +39=-81 \\ \\ z^2 + 16z=-120 \\ \\ z^2 + 16z+64=-56 \\ \\ \boxed{(z+8)^2=-56} \\ \\ z+8=\pm 2i√(14) \\ \\ \boxed{z=-8 \pm 2i√(14)}`