-4(x+2)(x+2)=-20

Solution for -4(x+2)(x+2)=-20 equation:

Simplifying
-4(x + 2)(x + 2) = -20

Reorder the terms:
-4(2 + x)(x + 2) = -20

Reorder the terms:
-4(2 + x)(2 + x) = -20

Multiply (2 + x) * (2 + x)
-4(2(2 + x) + x(2 + x)) = -20
-4((2 * 2 + x * 2) + x(2 + x)) = -20
-4((4 + 2x) + x(2 + x)) = -20
-4(4 + 2x + (2 * x + x * x)) = -20
-4(4 + 2x + (2x + x2)) = -20

Combine like terms: 2x + 2x = 4x
-4(4 + 4x + x2) = -20
(4 * -4 + 4x * -4 + x2 * -4) = -20
(-16 + -16x + -4x2) = -20

Solving
-16 + -16x + -4x2 = -20

Solving for variable 'x'.

Reorder the terms:
-16 + 20 + -16x + -4x2 = -20 + 20

Combine like terms: -16 + 20 = 4
4 + -16x + -4x2 = -20 + 20

Combine like terms: -20 + 20 = 0
4 + -16x + -4x2 = 0

Factor out the Greatest Common Factor (GCF), '4'.
4(1 + -4x + -1x2) = 0

Ignore the factor 4.
Subproblem 1
Set the factor '(1 + -4x + -1x2)' equal to zero and attempt to solve:

Simplifying
1 + -4x + -1x2 = 0

Solving
1 + -4x + -1x2 = 0

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

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

Move the constant term to the right:

Add '1' to each side of the equation.
-1 + 4x + 1 + x2 = 0 + 1

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

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

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

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 = 1 + 4

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

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

Factor a perfect square on the left side:
(x + 2)(x + 2) = 5

Calculate the square root of the right side: 2.236067978

Break this problem into two subproblems by setting 
(x + 2) equal to 2.236067978 and -2.236067978.

Subproblem 1
x + 2 = 2.236067978

Simplifying
x + 2 = 2.236067978

Reorder the terms:
2 + x = 2.236067978

Solving
2 + x = 2.236067978

Solving for variable 'x'.

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

Add '-2' to each side of the equation.
2 + -2 + x = 2.236067978 + -2

Combine like terms: 2 + -2 = 0
0 + x = 2.236067978 + -2
x = 2.236067978 + -2

Combine like terms: 2.236067978 + -2 = 0.236067978
x = 0.236067978

Simplifying
x = 0.236067978

Subproblem 2
x + 2 = -2.236067978

Simplifying
x + 2 = -2.236067978

Reorder the terms:
2 + x = -2.236067978

Solving
2 + x = -2.236067978

Solving for variable 'x'.

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

Add '-2' to each side of the equation.
2 + -2 + x = -2.236067978 + -2

Combine like terms: 2 + -2 = 0
0 + x = -2.236067978 + -2
x = -2.236067978 + -2

Combine like terms: -2.236067978 + -2 = -4.236067978
x = -4.236067978

Simplifying
x = -4.236067978

Solution
The solution to the problem is based on the solutions
from the subproblems.
x = {0.236067978, -4.236067978}
Solution
x = {0.236067978, -4.236067978}