a^2-(-7a)+12=0

Solution for a^2-(-7a)+12=0 equation:

Simplifying
a2 + -1(-7a) + 12 = 0

Remove parenthesis around (-7a)
a2 + -1 * -7a + 12 = 0

Multiply -1 * -7
a2 + 7a + 12 = 0

Reorder the terms:
12 + 7a + a2 = 0

Solving
12 + 7a + a2 = 0

Solving for variable 'a'.

Factor a trinomial.
(4 + a)(3 + a) = 0

Subproblem 1
Set the factor '(4 + a)' equal to zero and attempt to solve:

Simplifying
4 + a = 0

Solving
4 + a = 0

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

Add '-4' to each side of the equation.
4 + -4 + a = 0 + -4

Combine like terms: 4 + -4 = 0
0 + a = 0 + -4
a = 0 + -4

Combine like terms: 0 + -4 = -4
a = -4

Simplifying
a = -4
Subproblem 2
Set the factor '(3 + a)' equal to zero and attempt to solve:

Simplifying
3 + a = 0

Solving
3 + a = 0

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

Add '-3' to each side of the equation.
3 + -3 + a = 0 + -3

Combine like terms: 3 + -3 = 0
0 + a = 0 + -3
a = 0 + -3

Combine like terms: 0 + -3 = -3
a = -3

Simplifying
a = -3
Solution
a = {-4, -3}