-28b^2+136b+20=

Solution for -28b^2+136b+20= equation:

Simplifying
-28b2 + 136b + 20 = 0

Reorder the terms:
20 + 136b + -28b2 = 0

Solving
20 + 136b + -28b2 = 0

Solving for variable 'b'.

Factor out the Greatest Common Factor (GCF), '4'.
4(5 + 34b + -7b2) = 0

Factor a trinomial.
4((5 + -1b)(1 + 7b)) = 0

Ignore the factor 4.
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 '(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 = {5, -0.1428571429}