-4x^2-16x=-20

Solution for -4x^2-16x=-20 equation:

Simplifying
-4x2 + -16x = -20

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

Solving
-16x + -4x2 = -20

Solving for variable 'x'.

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

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

Factor out the Greatest Common Factor (GCF), '4'.
4(5 + -4x + -1x2) = 0

Factor a trinomial.
4((1 + -1x)(5 + x)) = 0

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

Simplifying
1 + -1x = 0

Solving
1 + -1x = 0

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

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

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

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

Divide each side by '-1'.
x = 1

Simplifying
x = 1
Subproblem 2
Set the factor '(5 + x)' equal to zero and attempt to solve:

Simplifying
5 + x = 0

Solving
5 + x = 0

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

Add '-5' to each side of the equation.
5 + -5 + x = 0 + -5

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

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

Simplifying
x = -5
Solution
x = {1, -5}