(b-36)(b+81)=0

Solution for (b-36)(b+81)=0 equation:

Simplifying
(b + -36)(b + 81) = 0

Reorder the terms:
(-36 + b)(b + 81) = 0

Reorder the terms:
(-36 + b)(81 + b) = 0

Multiply (-36 + b) * (81 + b)
(-36(81 + b) + b(81 + b)) = 0
((81 * -36 + b * -36) + b(81 + b)) = 0
((-2916 + -36b) + b(81 + b)) = 0
(-2916 + -36b + (81 * b + b * b)) = 0
(-2916 + -36b + (81b + b2)) = 0

Combine like terms: -36b + 81b = 45b
(-2916 + 45b + b2) = 0

Solving
-2916 + 45b + b2 = 0

Solving for variable 'b'.

Factor a trinomial.
(-81 + -1b)(36 + -1b) = 0

Subproblem 1
Set the factor '(-81 + -1b)' equal to zero and attempt to solve:

Simplifying
-81 + -1b = 0

Solving
-81 + -1b = 0

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

Add '81' to each side of the equation.
-81 + 81 + -1b = 0 + 81

Combine like terms: -81 + 81 = 0
0 + -1b = 0 + 81
-1b = 0 + 81

Combine like terms: 0 + 81 = 81
-1b = 81

Divide each side by '-1'.
b = -81

Simplifying
b = -81
Subproblem 2
Set the factor '(36 + -1b)' equal to zero and attempt to solve:

Simplifying
36 + -1b = 0

Solving
36 + -1b = 0

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

Add '-36' to each side of the equation.
36 + -36 + -1b = 0 + -36

Combine like terms: 36 + -36 = 0
0 + -1b = 0 + -36
-1b = 0 + -36

Combine like terms: 0 + -36 = -36
-1b = -36

Divide each side by '-1'.
b = 36

Simplifying
b = 36
Solution
b = {-81, 36}