(b-8)(b+5)=

Solution for (b-8)(b+5)= equation:

Simplifying
(b + -8)(b + 5) = 0

Reorder the terms:
(-8 + b)(b + 5) = 0

Reorder the terms:
(-8 + b)(5 + b) = 0

Multiply (-8 + b) * (5 + b)
(-8(5 + b) + b(5 + b)) = 0
((5 * -8 + b * -8) + b(5 + b)) = 0
((-40 + -8b) + b(5 + b)) = 0
(-40 + -8b + (5 * b + b * b)) = 0
(-40 + -8b + (5b + b2)) = 0

Combine like terms: -8b + 5b = -3b
(-40 + -3b + b2) = 0

Solving
-40 + -3b + b2 = 0

Solving for variable 'b'.

Factor a trinomial.
(-5 + -1b)(8 + -1b) = 0

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

Simplifying
-5 + -1b = 0

Solving
-5 + -1b = 0

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

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

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

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

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

Simplifying
b = -5
Subproblem 2
Set the factor '(8 + -1b)' equal to zero and attempt to solve:

Simplifying
8 + -1b = 0

Solving
8 + -1b = 0

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

Add '-8' to each side of the equation.
8 + -8 + -1b = 0 + -8

Combine like terms: 8 + -8 = 0
0 + -1b = 0 + -8
-1b = 0 + -8

Combine like terms: 0 + -8 = -8
-1b = -8

Divide each side by '-1'.
b = 8

Simplifying
b = 8
Solution
b = {-5, 8}