z^2-0.4z+1=0

Solution for z^2-0.4z+1=0 equation:

Simplifying
z2 + -0.4z + 1 = 0

Reorder the terms:
1 + -0.4z + z2 = 0

Solving
1 + -0.4z + z2 = 0

Solving for variable 'z'.

Begin completing the square.

Move the constant term to the right:

Add '-1' to each side of the equation.
1 + -0.4z + -1 + z2 = 0 + -1

Reorder the terms:
1 + -1 + -0.4z + z2 = 0 + -1

Combine like terms: 1 + -1 = 0
0 + -0.4z + z2 = 0 + -1
-0.4z + z2 = 0 + -1

Combine like terms: 0 + -1 = -1
-0.4z + z2 = -1

The z term is -0.4z.  Take half its coefficient (-0.2).
Square it (0.04) and add it to both sides.

Add '0.04' to each side of the equation.
-0.4z + 0.04 + z2 = -1 + 0.04

Reorder the terms:
0.04 + -0.4z + z2 = -1 + 0.04

Combine like terms: -1 + 0.04 = -0.96
0.04 + -0.4z + z2 = -0.96

Factor a perfect square on the left side:
(z + -0.2)(z + -0.2) = -0.96

Can't calculate square root of the right side.

The solution to this equation could not be determined.