10c+9+c^2=0

Solution for 10c+9+c^2=0 equation:

Simplifying
10c + 9 + c2 = 0

Reorder the terms:
9 + 10c + c2 = 0

Solving
9 + 10c + c2 = 0

Solving for variable 'c'.

Factor a trinomial.
(9 + c)(1 + c) = 0

Subproblem 1
Set the factor '(9 + c)' equal to zero and attempt to solve:

Simplifying
9 + c = 0

Solving
9 + c = 0

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

Add '-9' to each side of the equation.
9 + -9 + c = 0 + -9

Combine like terms: 9 + -9 = 0
0 + c = 0 + -9
c = 0 + -9

Combine like terms: 0 + -9 = -9
c = -9

Simplifying
c = -9
Subproblem 2
Set the factor '(1 + c)' equal to zero and attempt to solve:

Simplifying
1 + c = 0

Solving
1 + c = 0

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

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

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

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

Simplifying
c = -1
Solution
c = {-9, -1}