(5x+4)x-3=0.2*25x-4

Solution for (5x+4)x-3=0.2*25x-4 equation:

Simplifying
(5x + 4) * x + -3 = 0.2 * 25x + -4

Reorder the terms:
(4 + 5x) * x + -3 = 0.2 * 25x + -4

Reorder the terms for easier multiplication:
x(4 + 5x) + -3 = 0.2 * 25x + -4
(4 * x + 5x * x) + -3 = 0.2 * 25x + -4
(4x + 5x2) + -3 = 0.2 * 25x + -4

Reorder the terms:
-3 + 4x + 5x2 = 0.2 * 25x + -4

Multiply 0.2 * 25
-3 + 4x + 5x2 = 5x + -4

Reorder the terms:
-3 + 4x + 5x2 = -4 + 5x

Solving
-3 + 4x + 5x2 = -4 + 5x

Solving for variable 'x'.

Reorder the terms:
-3 + 4 + 4x + -5x + 5x2 = -4 + 5x + 4 + -5x

Combine like terms: -3 + 4 = 1
1 + 4x + -5x + 5x2 = -4 + 5x + 4 + -5x

Combine like terms: 4x + -5x = -1x
1 + -1x + 5x2 = -4 + 5x + 4 + -5x

Reorder the terms:
1 + -1x + 5x2 = -4 + 4 + 5x + -5x

Combine like terms: -4 + 4 = 0
1 + -1x + 5x2 = 0 + 5x + -5x
1 + -1x + 5x2 = 5x + -5x

Combine like terms: 5x + -5x = 0
1 + -1x + 5x2 = 0

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

Divide each side by '5'.
0.2 + -0.2x + x2 = 0

Move the constant term to the right:

Add '-0.2' to each side of the equation.
0.2 + -0.2x + -0.2 + x2 = 0 + -0.2

Reorder the terms:
0.2 + -0.2 + -0.2x + x2 = 0 + -0.2

Combine like terms: 0.2 + -0.2 = 0.0
0.0 + -0.2x + x2 = 0 + -0.2
-0.2x + x2 = 0 + -0.2

Combine like terms: 0 + -0.2 = -0.2
-0.2x + x2 = -0.2

The x term is -0.2x.  Take half its coefficient (-0.1).
Square it (0.01) and add it to both sides.

Add '0.01' to each side of the equation.
-0.2x + 0.01 + x2 = -0.2 + 0.01

Reorder the terms:
0.01 + -0.2x + x2 = -0.2 + 0.01

Combine like terms: -0.2 + 0.01 = -0.19
0.01 + -0.2x + x2 = -0.19

Factor a perfect square on the left side:
(x + -0.1)(x + -0.1) = -0.19

Can't calculate square root of the right side.

The solution to this equation could not be determined.