(x^2-x+4)-(3x^2+x-2)=0

Solution for (x^2-x+4)-(3x^2+x-2)=0 equation:

Simplifying
(x2 + -1x + 4) + -1(3x2 + x + -2) = 0

Reorder the terms:
(4 + -1x + x2) + -1(3x2 + x + -2) = 0

Remove parenthesis around (4 + -1x + x2)
4 + -1x + x2 + -1(3x2 + x + -2) = 0

Reorder the terms:
4 + -1x + x2 + -1(-2 + x + 3x2) = 0
4 + -1x + x2 + (-2 * -1 + x * -1 + 3x2 * -1) = 0
4 + -1x + x2 + (2 + -1x + -3x2) = 0

Reorder the terms:
4 + 2 + -1x + -1x + x2 + -3x2 = 0

Combine like terms: 4 + 2 = 6
6 + -1x + -1x + x2 + -3x2 = 0

Combine like terms: -1x + -1x = -2x
6 + -2x + x2 + -3x2 = 0

Combine like terms: x2 + -3x2 = -2x2
6 + -2x + -2x2 = 0

Solving
6 + -2x + -2x2 = 0

Solving for variable 'x'.

Factor out the Greatest Common Factor (GCF), '2'.
2(3 + -1x + -1x2) = 0

Ignore the factor 2.
Subproblem 1
Set the factor '(3 + -1x + -1x2)' equal to zero and attempt to solve:

Simplifying
3 + -1x + -1x2 = 0

Solving
3 + -1x + -1x2 = 0

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

Divide each side by '-1'.
-3 + x + x2 = 0

Move the constant term to the right:

Add '3' to each side of the equation.
-3 + x + 3 + x2 = 0 + 3

Reorder the terms:
-3 + 3 + x + x2 = 0 + 3

Combine like terms: -3 + 3 = 0
0 + x + x2 = 0 + 3
x + x2 = 0 + 3

Combine like terms: 0 + 3 = 3
x + x2 = 3

The x term is x.  Take half its coefficient (0.5).
Square it (0.25) and add it to both sides.

Add '0.25' to each side of the equation.
 + 0.25 + x2 = 3 + 0.25

Combine like terms:  + 0.25 = 1.25
1.25 + x2 = 3 + 0.25

Combine like terms: 3 + 0.25 = 3.25
1.25 + x2 = 3.25

Factor a perfect square on the left side:
(x + 0.5)(x + 0.5) = 3.25

Calculate the square root of the right side: 1.802775638

Break this problem into two subproblems by setting 
(x + 0.5) equal to 1.802775638 and -1.802775638.

Subproblem 1
x + 0.5 = 1.802775638

Simplifying
x + 0.5 = 1.802775638

Reorder the terms:
0.5 + x = 1.802775638

Solving
0.5 + x = 1.802775638

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '-0.5' to each side of the equation.
0.5 + -0.5 + x = 1.802775638 + -0.5

Combine like terms: 0.5 + -0.5 = 0.0
0.0 + x = 1.802775638 + -0.5
x = 1.802775638 + -0.5

Combine like terms: 1.802775638 + -0.5 = 1.302775638
x = 1.302775638

Simplifying
x = 1.302775638

Subproblem 2
x + 0.5 = -1.802775638

Simplifying
x + 0.5 = -1.802775638

Reorder the terms:
0.5 + x = -1.802775638

Solving
0.5 + x = -1.802775638

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '-0.5' to each side of the equation.
0.5 + -0.5 + x = -1.802775638 + -0.5

Combine like terms: 0.5 + -0.5 = 0.0
0.0 + x = -1.802775638 + -0.5
x = -1.802775638 + -0.5

Combine like terms: -1.802775638 + -0.5 = -2.302775638
x = -2.302775638

Simplifying
x = -2.302775638

Solution
The solution to the problem is based on the solutions
from the subproblems.
x = {1.302775638, -2.302775638}
Solution
x = {1.302775638, -2.302775638}