(2s+5)(s+4)=0

Solution for (2s+5)(s+4)=0 equation:

Simplifying
(2s + 5)(s + 4) = 0

Reorder the terms:
(5 + 2s)(s + 4) = 0

Reorder the terms:
(5 + 2s)(4 + s) = 0

Multiply (5 + 2s) * (4 + s)
(5(4 + s) + 2s * (4 + s)) = 0
((4 * 5 + s * 5) + 2s * (4 + s)) = 0
((20 + 5s) + 2s * (4 + s)) = 0
(20 + 5s + (4 * 2s + s * 2s)) = 0
(20 + 5s + (8s + 2s2)) = 0

Combine like terms: 5s + 8s = 13s
(20 + 13s + 2s2) = 0

Solving
20 + 13s + 2s2 = 0

Solving for variable 's'.

Factor a trinomial.
(4 + s)(5 + 2s) = 0

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

Simplifying
4 + s = 0

Solving
4 + s = 0

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

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

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

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

Simplifying
s = -4
Subproblem 2
Set the factor '(5 + 2s)' equal to zero and attempt to solve:

Simplifying
5 + 2s = 0

Solving
5 + 2s = 0

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

Add '-5' to each side of the equation.
5 + -5 + 2s = 0 + -5

Combine like terms: 5 + -5 = 0
0 + 2s = 0 + -5
2s = 0 + -5

Combine like terms: 0 + -5 = -5
2s = -5

Divide each side by '2'.
s = -2.5

Simplifying
s = -2.5
Solution
s = {-4, -2.5}