20b^2-b-1=0

Solution for 20b^2-b-1=0 equation:

Simplifying
20b2 + -1b + -1 = 0

Reorder the terms:
-1 + -1b + 20b2 = 0

Solving
-1 + -1b + 20b2 = 0

Solving for variable 'b'.

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

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

Simplifying
-1 + -5b = 0

Solving
-1 + -5b = 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 + -5b = 0 + 1

Combine like terms: -1 + 1 = 0
0 + -5b = 0 + 1
-5b = 0 + 1

Combine like terms: 0 + 1 = 1
-5b = 1

Divide each side by '-5'.
b = -0.2

Simplifying
b = -0.2
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 = {-0.2, 0.25}