(4-x)=3x^2+7

Solution for (4-x)=3x^2+7 equation:

Simplifying
(4 + -1x) = 3x2 + 7

Remove parenthesis around (4 + -1x)
4 + -1x = 3x2 + 7

Reorder the terms:
4 + -1x = 7 + 3x2

Solving
4 + -1x = 7 + 3x2

Solving for variable 'x'.

Reorder the terms:
4 + -7 + -1x + -3x2 = 7 + 3x2 + -7 + -3x2

Combine like terms: 4 + -7 = -3
-3 + -1x + -3x2 = 7 + 3x2 + -7 + -3x2

Reorder the terms:
-3 + -1x + -3x2 = 7 + -7 + 3x2 + -3x2

Combine like terms: 7 + -7 = 0
-3 + -1x + -3x2 = 0 + 3x2 + -3x2
-3 + -1x + -3x2 = 3x2 + -3x2

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

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

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

Simplifying
3 + x + 3x2 = 0

Solving
3 + x + 3x2 = 0

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

Divide each side by '3'.
1 + 0.3333333333x + x2 = 0

Move the constant term to the right:

Add '-1' to each side of the equation.
1 + 0.3333333333x + -1 + x2 = 0 + -1

Reorder the terms:
1 + -1 + 0.3333333333x + x2 = 0 + -1

Combine like terms: 1 + -1 = 0
0 + 0.3333333333x + x2 = 0 + -1
0.3333333333x + x2 = 0 + -1

Combine like terms: 0 + -1 = -1
0.3333333333x + x2 = -1

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.
0.3333333333x + 0.25 + x2 = -1 + 0.25

Reorder the terms:
0.25 + 0.3333333333x + x2 = -1 + 0.25

Combine like terms: -1 + 0.25 = -0.75
0.25 + 0.3333333333x + x2 = -0.75

Factor a perfect square on the left side:
(x + 0.5)(x + 0.5) = -0.75

Can't calculate square root of the right side.

The solution to this equation could not be determined.

This subproblem is being ignored because a solution could not be determined.

The solution to this equation could not be determined.