2k^2-8k-99=-9

Solution for 2k^2-8k-99=-9 equation:

Simplifying
2k2 + -8k + -99 = -9

Reorder the terms:
-99 + -8k + 2k2 = -9

Solving
-99 + -8k + 2k2 = -9

Solving for variable 'k'.

Reorder the terms:
-99 + 9 + -8k + 2k2 = -9 + 9

Combine like terms: -99 + 9 = -90
-90 + -8k + 2k2 = -9 + 9

Combine like terms: -9 + 9 = 0
-90 + -8k + 2k2 = 0

Factor out the Greatest Common Factor (GCF), '2'.
2(-45 + -4k + k2) = 0

Factor a trinomial.
2((-5 + -1k)(9 + -1k)) = 0

Ignore the factor 2.
Subproblem 1
Set the factor '(-5 + -1k)' equal to zero and attempt to solve:

Simplifying
-5 + -1k = 0

Solving
-5 + -1k = 0

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

Add '5' to each side of the equation.
-5 + 5 + -1k = 0 + 5

Combine like terms: -5 + 5 = 0
0 + -1k = 0 + 5
-1k = 0 + 5

Combine like terms: 0 + 5 = 5
-1k = 5

Divide each side by '-1'.
k = -5

Simplifying
k = -5
Subproblem 2
Set the factor '(9 + -1k)' equal to zero and attempt to solve:

Simplifying
9 + -1k = 0

Solving
9 + -1k = 0

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

Add '-9' to each side of the equation.
9 + -9 + -1k = 0 + -9

Combine like terms: 9 + -9 = 0
0 + -1k = 0 + -9
-1k = 0 + -9

Combine like terms: 0 + -9 = -9
-1k = -9

Divide each side by '-1'.
k = 9

Simplifying
k = 9
Solution
k = {-5, 9}