0=20+m-m^2

Solution for 0=20+m-m^2 equation:

Simplifying
0 = 20 + m + -1m2

Solving
0 = 20 + m + -1m2

Solving for variable 'm'.

Combine like terms: 0 + -20 = -20
-20 + -1m + m2 = 20 + m + -1m2 + -20 + -1m + m2

Reorder the terms:
-20 + -1m + m2 = 20 + -20 + m + -1m + -1m2 + m2

Combine like terms: 20 + -20 = 0
-20 + -1m + m2 = 0 + m + -1m + -1m2 + m2
-20 + -1m + m2 = m + -1m + -1m2 + m2

Combine like terms: m + -1m = 0
-20 + -1m + m2 = 0 + -1m2 + m2
-20 + -1m + m2 = -1m2 + m2

Combine like terms: -1m2 + m2 = 0
-20 + -1m + m2 = 0

Factor a trinomial.
(-4 + -1m)(5 + -1m) = 0

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

Simplifying
-4 + -1m = 0

Solving
-4 + -1m = 0

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

Add '4' to each side of the equation.
-4 + 4 + -1m = 0 + 4

Combine like terms: -4 + 4 = 0
0 + -1m = 0 + 4
-1m = 0 + 4

Combine like terms: 0 + 4 = 4
-1m = 4

Divide each side by '-1'.
m = -4

Simplifying
m = -4
Subproblem 2
Set the factor '(5 + -1m)' equal to zero and attempt to solve:

Simplifying
5 + -1m = 0

Solving
5 + -1m = 0

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

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

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

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

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

Simplifying
m = 5
Solution
m = {-4, 5}