4b^2+21b+5=

Solution for 4b^2+21b+5= equation:

Simplifying
4b2 + 21b + 5 = 0

Reorder the terms:
5 + 21b + 4b2 = 0

Solving
5 + 21b + 4b2 = 0

Solving for variable 'b'.

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

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

Simplifying
5 + b = 0

Solving
5 + b = 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 + b = 0 + -5

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

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

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

Simplifying
1 + 4b = 0

Solving
1 + 4b = 0

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

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

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

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

Divide each side by '4'.
b = -0.25

Simplifying
b = -0.25
Solution
b = {-5, -0.25}