-4a^2(5a^2-4a+5)=

Solution for -4a^2(5a^2-4a+5)= equation:

Simplifying
-4a2(5a2 + -4a + 5) = 0

Reorder the terms:
-4a2(5 + -4a + 5a2) = 0
(5 * -4a2 + -4a * -4a2 + 5a2 * -4a2) = 0
(-20a2 + 16a3 + -20a4) = 0

Solving
-20a2 + 16a3 + -20a4 = 0

Solving for variable 'a'.

Factor out the Greatest Common Factor (GCF), '4a2'.
4a2(-5 + 4a + -5a2) = 0

Ignore the factor 4.
Subproblem 1
Set the factor 'a2' equal to zero and attempt to solve:

Simplifying
a2 = 0

Solving
a2 = 0

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

Simplifying
a2 = 0

Take the square root of each side:
a = {0}
Subproblem 2
Set the factor '(-5 + 4a + -5a2)' equal to zero and attempt to solve:

Simplifying
-5 + 4a + -5a2 = 0

Solving
-5 + 4a + -5a2 = 0

Begin completing the square.  Divide all terms by
-5 the coefficient of the squared term: 

Divide each side by '-5'.
1 + -0.8a + a2 = 0

Move the constant term to the right:

Add '-1' to each side of the equation.
1 + -0.8a + -1 + a2 = 0 + -1

Reorder the terms:
1 + -1 + -0.8a + a2 = 0 + -1

Combine like terms: 1 + -1 = 0
0 + -0.8a + a2 = 0 + -1
-0.8a + a2 = 0 + -1

Combine like terms: 0 + -1 = -1
-0.8a + a2 = -1

The a term is -0.8a.  Take half its coefficient (-0.4).
Square it (0.16) and add it to both sides.

Add '0.16' to each side of the equation.
-0.8a + 0.16 + a2 = -1 + 0.16

Reorder the terms:
0.16 + -0.8a + a2 = -1 + 0.16

Combine like terms: -1 + 0.16 = -0.84
0.16 + -0.8a + a2 = -0.84

Factor a perfect square on the left side:
(a + -0.4)(a + -0.4) = -0.84

Can't calculate square root of the right side.

The solution to this equation could not be determined.

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