ab^2-ab-20a=0

Solution for ab^2-ab-20a=0 equation:

Simplifying
ab2 + -1ab + -20a = 0

Reorder the terms:
-20a + -1ab + ab2 = 0

Solving
-20a + -1ab + ab2 = 0

Solving for variable 'a'.

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

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

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

Subproblem 1
Set the factor 'a' equal to zero and attempt to solve:

Simplifying
a = 0

Solving
a = 0

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

Simplifying
a = 0
Subproblem 2
Set the factor '(-4 + -1b)' equal to zero and attempt to solve:

Simplifying
-4 + -1b = 0

Solving
-4 + -1b = 0

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

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

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

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

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

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

Simplifying
0 = 4 + b

The solution to this equation could not be determined.

This subproblem is being ignored because a solution could not be determined.
Subproblem 3
Set the factor '(5 + -1b)' equal to zero and attempt to solve:

Simplifying
5 + -1b = 0

Solving
5 + -1b = 0

Move all terms containing a 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

Add 'b' to each side of the equation.
-1b + b = -5 + b

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

Simplifying
0 = -5 + b

The solution to this equation could not be determined.

This subproblem is being ignored because a solution could not be determined.
Solution
a = {0}