(-b-7)(b+3)=

Solution for (-b-7)(b+3)= equation:

Simplifying
(-1b + -7)(b + 3) = 0

Reorder the terms:
(-7 + -1b)(b + 3) = 0

Reorder the terms:
(-7 + -1b)(3 + b) = 0

Multiply (-7 + -1b) * (3 + b)
(-7(3 + b) + -1b * (3 + b)) = 0
((3 * -7 + b * -7) + -1b * (3 + b)) = 0
((-21 + -7b) + -1b * (3 + b)) = 0
(-21 + -7b + (3 * -1b + b * -1b)) = 0
(-21 + -7b + (-3b + -1b2)) = 0

Combine like terms: -7b + -3b = -10b
(-21 + -10b + -1b2) = 0

Solving
-21 + -10b + -1b2 = 0

Solving for variable 'b'.

Factor out the Greatest Common Factor (GCF), '-1'.
-1(21 + 10b + b2) = 0

Factor a trinomial.
-1((7 + b)(3 + b)) = 0

Ignore the factor -1.
Subproblem 1
Set the factor '(7 + b)' equal to zero and attempt to solve:

Simplifying
7 + b = 0

Solving
7 + b = 0

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

Add '-7' to each side of the equation.
7 + -7 + b = 0 + -7

Combine like terms: 7 + -7 = 0
0 + b = 0 + -7
b = 0 + -7

Combine like terms: 0 + -7 = -7
b = -7

Simplifying
b = -7
Subproblem 2
Set the factor '(3 + b)' equal to zero and attempt to solve:

Simplifying
3 + b = 0

Solving
3 + b = 0

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

Add '-3' to each side of the equation.
3 + -3 + b = 0 + -3

Combine like terms: 3 + -3 = 0
0 + b = 0 + -3
b = 0 + -3

Combine like terms: 0 + -3 = -3
b = -3

Simplifying
b = -3
Solution
b = {-7, -3}