-a^2-2a-6=-5

Solution for -a^2-2a-6=-5 equation:

Simplifying
-1a2 + -2a + -6 = -5

Reorder the terms:
-6 + -2a + -1a2 = -5

Solving
-6 + -2a + -1a2 = -5

Solving for variable 'a'.

Reorder the terms:
-6 + 5 + -2a + -1a2 = -5 + 5

Combine like terms: -6 + 5 = -1
-1 + -2a + -1a2 = -5 + 5

Combine like terms: -5 + 5 = 0
-1 + -2a + -1a2 = 0

Factor out the Greatest Common Factor (GCF), '-1'.
-1(1 + 2a + a2) = 0

Factor a trinomial.
-1((1 + a)(1 + a)) = 0

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

Simplifying
1 + a = 0

Solving
1 + a = 0

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

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

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

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

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

Simplifying
1 + a = 0

Solving
1 + a = 0

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

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

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

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

Simplifying
a = -1
Solution
a = {-1, -1}