.5(4x)(x-3)=30

Solution for .5(4x)(x-3)=30 equation:

Simplifying
0.5(4x)(x + -3) = 30

Remove parenthesis around (4x)
0.5 * 4x(x + -3) = 30

Reorder the terms:
0.5 * 4x(-3 + x) = 30

Multiply 0.5 * 4
2x(-3 + x) = 30
(-3 * 2x + x * 2x) = 30
(-6x + 2x2) = 30

Solving
-6x + 2x2 = 30

Solving for variable 'x'.

Reorder the terms:
-30 + -6x + 2x2 = 30 + -30

Combine like terms: 30 + -30 = 0
-30 + -6x + 2x2 = 0

Factor out the Greatest Common Factor (GCF), '2'.
2(-15 + -3x + x2) = 0

Ignore the factor 2.
Subproblem 1
Set the factor '(-15 + -3x + x2)' equal to zero and attempt to solve:

Simplifying
-15 + -3x + x2 = 0

Solving
-15 + -3x + x2 = 0

Begin completing the square.

Move the constant term to the right:

Add '15' to each side of the equation.
-15 + -3x + 15 + x2 = 0 + 15

Reorder the terms:
-15 + 15 + -3x + x2 = 0 + 15

Combine like terms: -15 + 15 = 0
0 + -3x + x2 = 0 + 15
-3x + x2 = 0 + 15

Combine like terms: 0 + 15 = 15
-3x + x2 = 15

The x term is -3x.  Take half its coefficient (-1.5).
Square it (2.25) and add it to both sides.

Add '2.25' to each side of the equation.
-3x + 2.25 + x2 = 15 + 2.25

Reorder the terms:
2.25 + -3x + x2 = 15 + 2.25

Combine like terms: 15 + 2.25 = 17.25
2.25 + -3x + x2 = 17.25

Factor a perfect square on the left side:
(x + -1.5)(x + -1.5) = 17.25

Calculate the square root of the right side: 4.153311931

Break this problem into two subproblems by setting 
(x + -1.5) equal to 4.153311931 and -4.153311931.

Subproblem 1
x + -1.5 = 4.153311931

Simplifying
x + -1.5 = 4.153311931

Reorder the terms:
-1.5 + x = 4.153311931

Solving
-1.5 + x = 4.153311931

Solving for variable 'x'.

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

Add '1.5' to each side of the equation.
-1.5 + 1.5 + x = 4.153311931 + 1.5

Combine like terms: -1.5 + 1.5 = 0.0
0.0 + x = 4.153311931 + 1.5
x = 4.153311931 + 1.5

Combine like terms: 4.153311931 + 1.5 = 5.653311931
x = 5.653311931

Simplifying
x = 5.653311931

Subproblem 2
x + -1.5 = -4.153311931

Simplifying
x + -1.5 = -4.153311931

Reorder the terms:
-1.5 + x = -4.153311931

Solving
-1.5 + x = -4.153311931

Solving for variable 'x'.

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

Add '1.5' to each side of the equation.
-1.5 + 1.5 + x = -4.153311931 + 1.5

Combine like terms: -1.5 + 1.5 = 0.0
0.0 + x = -4.153311931 + 1.5
x = -4.153311931 + 1.5

Combine like terms: -4.153311931 + 1.5 = -2.653311931
x = -2.653311931

Simplifying
x = -2.653311931

Solution
The solution to the problem is based on the solutions
from the subproblems.
x = {5.653311931, -2.653311931}
Solution
x = {5.653311931, -2.653311931}