-s^2+8s+9=0

Solution for -s^2+8s+9=0 equation:

Simplifying
-1s2 + 8s + 9 = 0

Reorder the terms:
9 + 8s + -1s2 = 0

Solving
9 + 8s + -1s2 = 0

Solving for variable 's'.

Factor a trinomial.
(9 + -1s)(1 + s) = 0

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

Simplifying
9 + -1s = 0

Solving
9 + -1s = 0

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

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

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

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

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

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

Simplifying
1 + s = 0

Solving
1 + s = 0

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

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

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

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

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