K^2+22K+21=0

Solution for K^2+22K+21=0 equation:

Simplifying
K2 + 22K + 21 = 0

Reorder the terms:
21 + 22K + K2 = 0

Solving
21 + 22K + K2 = 0

Solving for variable 'K'.

Factor a trinomial.
(21 + K)(1 + K) = 0

Subproblem 1
Set the factor '(21 + K)' equal to zero and attempt to solve:

Simplifying
21 + K = 0

Solving
21 + K = 0

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

Add '-21' to each side of the equation.
21 + -21 + K = 0 + -21

Combine like terms: 21 + -21 = 0
0 + K = 0 + -21
K = 0 + -21

Combine like terms: 0 + -21 = -21
K = -21

Simplifying
K = -21
Subproblem 2
Set the factor '(1 + K)' equal to zero and attempt to solve:

Simplifying
1 + K = 0

Solving
1 + K = 0

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

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

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

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

Simplifying
K = -1
Solution
K = {-21, -1}