0=800-8x+0.25x^2

Solution for 0=800-8x+0.25x^2 equation:

Simplifying
0 = 800 + -8x + 0.25x2

Solving
0 = 800 + -8x + 0.25x2

Solving for variable 'x'.

Combine like terms: 0 + -800 = -800
-800 + 8x + -0.25x2 = 800 + -8x + 0.25x2 + -800 + 8x + -0.25x2

Reorder the terms:
-800 + 8x + -0.25x2 = 800 + -800 + -8x + 8x + 0.25x2 + -0.25x2

Combine like terms: 800 + -800 = 0
-800 + 8x + -0.25x2 = 0 + -8x + 8x + 0.25x2 + -0.25x2
-800 + 8x + -0.25x2 = -8x + 8x + 0.25x2 + -0.25x2

Combine like terms: -8x + 8x = 0
-800 + 8x + -0.25x2 = 0 + 0.25x2 + -0.25x2
-800 + 8x + -0.25x2 = 0.25x2 + -0.25x2

Combine like terms: 0.25x2 + -0.25x2 = 0.00
-800 + 8x + -0.25x2 = 0.00

Begin completing the square.  Divide all terms by
-0.25 the coefficient of the squared term: 

Divide each side by '-0.25'.
3200 + -32x + x2 = 0

Move the constant term to the right:

Add '-3200' to each side of the equation.
3200 + -32x + -3200 + x2 = 0 + -3200

Reorder the terms:
3200 + -3200 + -32x + x2 = 0 + -3200

Combine like terms: 3200 + -3200 = 0
0 + -32x + x2 = 0 + -3200
-32x + x2 = 0 + -3200

Combine like terms: 0 + -3200 = -3200
-32x + x2 = -3200

The x term is -32x.  Take half its coefficient (-16).
Square it (256) and add it to both sides.

Add '256' to each side of the equation.
-32x + 256 + x2 = -3200 + 256

Reorder the terms:
256 + -32x + x2 = -3200 + 256

Combine like terms: -3200 + 256 = -2944
256 + -32x + x2 = -2944

Factor a perfect square on the left side:
(x + -16)(x + -16) = -2944

Can't calculate square root of the right side.

The solution to this equation could not be determined.