s(s-4)=45

Solution for s(s-4)=45 equation:

Simplifying
s(s + -4) = 45

Reorder the terms:
s(-4 + s) = 45
(-4 * s + s * s) = 45
(-4s + s2) = 45

Solving
-4s + s2 = 45

Solving for variable 's'.

Reorder the terms:
-45 + -4s + s2 = 45 + -45

Combine like terms: 45 + -45 = 0
-45 + -4s + s2 = 0

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

Subproblem 1
Set the factor '(-5 + -1s)' equal to zero and attempt to solve:

Simplifying
-5 + -1s = 0

Solving
-5 + -1s = 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 + -1s = 0 + 5

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

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

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

Simplifying
s = -5
Subproblem 2
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
Solution
s = {-5, 9}