-z^2+2z-5=0

Solution for -z^2+2z-5=0 equation:

Simplifying
-1z2 + 2z + -5 = 0

Reorder the terms:
-5 + 2z + -1z2 = 0

Solving
-5 + 2z + -1z2 = 0

Solving for variable 'z'.

Begin completing the square.  Divide all terms by
-1 the coefficient of the squared term: 

Divide each side by '-1'.
5 + -2z + z2 = 0

Move the constant term to the right:

Add '-5' to each side of the equation.
5 + -2z + -5 + z2 = 0 + -5

Reorder the terms:
5 + -5 + -2z + z2 = 0 + -5

Combine like terms: 5 + -5 = 0
0 + -2z + z2 = 0 + -5
-2z + z2 = 0 + -5

Combine like terms: 0 + -5 = -5
-2z + z2 = -5

The z term is -2z.  Take half its coefficient (-1).
Square it (1) and add it to both sides.

Add '1' to each side of the equation.
-2z + 1 + z2 = -5 + 1

Reorder the terms:
1 + -2z + z2 = -5 + 1

Combine like terms: -5 + 1 = -4
1 + -2z + z2 = -4

Factor a perfect square on the left side:
(z + -1)(z + -1) = -4

Can't calculate square root of the right side.

The solution to this equation could not be determined.