-4(5+5b)b=43

Solution for -4(5+5b)b=43 equation:

Simplifying
-4(5 + 5b) * b = 43

Reorder the terms for easier multiplication:
-4b(5 + 5b) = 43
(5 * -4b + 5b * -4b) = 43
(-20b + -20b2) = 43

Solving
-20b + -20b2 = 43

Solving for variable 'b'.

Reorder the terms:
-43 + -20b + -20b2 = 43 + -43

Combine like terms: 43 + -43 = 0
-43 + -20b + -20b2 = 0

Factor out the Greatest Common Factor (GCF), '-1'.
-1(43 + 20b + 20b2) = 0

Ignore the factor -1.
Subproblem 1
Set the factor '(43 + 20b + 20b2)' equal to zero and attempt to solve:

Simplifying
43 + 20b + 20b2 = 0

Solving
43 + 20b + 20b2 = 0

Begin completing the square.  Divide all terms by
20 the coefficient of the squared term: 

Divide each side by '20'.
2.15 + b + b2 = 0.0

Move the constant term to the right:

Add '-2.15' to each side of the equation.
2.15 + b + -2.15 + b2 = 0.0 + -2.15

Reorder the terms:
2.15 + -2.15 + b + b2 = 0.0 + -2.15

Combine like terms: 2.15 + -2.15 = 0.00
0.00 + b + b2 = 0.0 + -2.15
b + b2 = 0.0 + -2.15

Combine like terms: 0.0 + -2.15 = -2.15
b + b2 = -2.15

The b term is b.  Take half its coefficient (0.5).
Square it (0.25) and add it to both sides.

Add '0.25' to each side of the equation.
 + 0.25 + b2 = -2.15 + 0.25

Combine like terms:  + 0.25 = 1.25
1.25 + b2 = -2.15 + 0.25

Combine like terms: -2.15 + 0.25 = -1.9
1.25 + b2 = -1.9

Factor a perfect square on the left side:
(b + 0.5)(b + 0.5) = -1.9

Can't calculate square root of the right side.

The solution to this equation could not be determined.

This subproblem is being ignored because a solution could not be determined.

The solution to this equation could not be determined.