-21b^2+39b+6=

Solution for -21b^2+39b+6= equation:

Simplifying
-21b2 + 39b + 6 = 0

Reorder the terms:
6 + 39b + -21b2 = 0

Solving
6 + 39b + -21b2 = 0

Solving for variable 'b'.

Factor out the Greatest Common Factor (GCF), '3'.
3(2 + 13b + -7b2) = 0

Factor a trinomial.
3((2 + -1b)(1 + 7b)) = 0

Ignore the factor 3.
Subproblem 1
Set the factor '(2 + -1b)' equal to zero and attempt to solve:

Simplifying
2 + -1b = 0

Solving
2 + -1b = 0

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

Add '-2' to each side of the equation.
2 + -2 + -1b = 0 + -2

Combine like terms: 2 + -2 = 0
0 + -1b = 0 + -2
-1b = 0 + -2

Combine like terms: 0 + -2 = -2
-1b = -2

Divide each side by '-1'.
b = 2

Simplifying
b = 2
Subproblem 2
Set the factor '(1 + 7b)' equal to zero and attempt to solve:

Simplifying
1 + 7b = 0

Solving
1 + 7b = 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 + 7b = 0 + -1

Combine like terms: 1 + -1 = 0
0 + 7b = 0 + -1
7b = 0 + -1

Combine like terms: 0 + -1 = -1
7b = -1

Divide each side by '7'.
b = -0.1428571429

Simplifying
b = -0.1428571429
Solution
b = {2, -0.1428571429}