4x=x^2+42

Solution for 4x=x^2+42 equation:

Simplifying
4x = x2 + 42

Reorder the terms:
4x = 42 + x2

Solving
4x = 42 + x2

Solving for variable 'x'.

Reorder the terms:
-42 + 4x + -1x2 = 42 + x2 + -42 + -1x2

Reorder the terms:
-42 + 4x + -1x2 = 42 + -42 + x2 + -1x2

Combine like terms: 42 + -42 = 0
-42 + 4x + -1x2 = 0 + x2 + -1x2
-42 + 4x + -1x2 = x2 + -1x2

Combine like terms: x2 + -1x2 = 0
-42 + 4x + -1x2 = 0

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

Divide each side by '-1'.
42 + -4x + x2 = 0

Move the constant term to the right:

Add '-42' to each side of the equation.
42 + -4x + -42 + x2 = 0 + -42

Reorder the terms:
42 + -42 + -4x + x2 = 0 + -42

Combine like terms: 42 + -42 = 0
0 + -4x + x2 = 0 + -42
-4x + x2 = 0 + -42

Combine like terms: 0 + -42 = -42
-4x + x2 = -42

The x term is -4x.  Take half its coefficient (-2).
Square it (4) and add it to both sides.

Add '4' to each side of the equation.
-4x + 4 + x2 = -42 + 4

Reorder the terms:
4 + -4x + x2 = -42 + 4

Combine like terms: -42 + 4 = -38
4 + -4x + x2 = -38

Factor a perfect square on the left side:
(x + -2)(x + -2) = -38

Can't calculate square root of the right side.

The solution to this equation could not be determined.