=(x-1.5)(x+1.2)

Solution for =(x-1.5)(x+1.2) equation:

Simplifying
0 = (x + -1.5)(x + 1.2)

Reorder the terms:
0 = (-1.5 + x)(x + 1.2)

Reorder the terms:
0 = (-1.5 + x)(1.2 + x)

Multiply (-1.5 + x) * (1.2 + x)
0 = (-1.5(1.2 + x) + x(1.2 + x))
0 = ((1.2 * -1.5 + x * -1.5) + x(1.2 + x))
0 = ((-1.8 + -1.5x) + x(1.2 + x))
0 = (-1.8 + -1.5x + (1.2 * x + x * x))
0 = (-1.8 + -1.5x + (1.2x + x2))

Combine like terms: -1.5x + 1.2x = -0.3x
0 = (-1.8 + -0.3x + x2)

Solving
0 = -1.8 + -0.3x + x2

Solving for variable 'x'.

Combine like terms: 0 + 1.8 = 1.8
1.8 + 0.3x + -1x2 = -1.8 + -0.3x + x2 + 1.8 + 0.3x + -1x2

Reorder the terms:
1.8 + 0.3x + -1x2 = -1.8 + 1.8 + -0.3x + 0.3x + x2 + -1x2

Combine like terms: -1.8 + 1.8 = 0.0
1.8 + 0.3x + -1x2 = 0.0 + -0.3x + 0.3x + x2 + -1x2
1.8 + 0.3x + -1x2 = -0.3x + 0.3x + x2 + -1x2

Combine like terms: -0.3x + 0.3x = 0.0
1.8 + 0.3x + -1x2 = 0.0 + x2 + -1x2
1.8 + 0.3x + -1x2 = x2 + -1x2

Combine like terms: x2 + -1x2 = 0
1.8 + 0.3x + -1x2 = 0

Begin completing the square.  Divide all terms by
-1 the coefficient of the squared term: 

Divide each side by '-1'.
-1.8 + -0.3x + x2 = 0

Move the constant term to the right:

Add '1.8' to each side of the equation.
-1.8 + -0.3x + 1.8 + x2 = 0 + 1.8

Reorder the terms:
-1.8 + 1.8 + -0.3x + x2 = 0 + 1.8

Combine like terms: -1.8 + 1.8 = 0.0
0.0 + -0.3x + x2 = 0 + 1.8
-0.3x + x2 = 0 + 1.8

Combine like terms: 0 + 1.8 = 1.8
-0.3x + x2 = 1.8

The x term is -0.3x.  Take half its coefficient (-0.15).
Square it (0.0225) and add it to both sides.

Add '0.0225' to each side of the equation.
-0.3x + 0.0225 + x2 = 1.8 + 0.0225

Reorder the terms:
0.0225 + -0.3x + x2 = 1.8 + 0.0225

Combine like terms: 1.8 + 0.0225 = 1.8225
0.0225 + -0.3x + x2 = 1.8225

Factor a perfect square on the left side:
(x + -0.15)(x + -0.15) = 1.8225

Calculate the square root of the right side: 1.35

Break this problem into two subproblems by setting 
(x + -0.15) equal to 1.35 and -1.35.

Subproblem 1
x + -0.15 = 1.35

Simplifying
x + -0.15 = 1.35

Reorder the terms:
-0.15 + x = 1.35

Solving
-0.15 + x = 1.35

Solving for variable 'x'.

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

Add '0.15' to each side of the equation.
-0.15 + 0.15 + x = 1.35 + 0.15

Combine like terms: -0.15 + 0.15 = 0.00
0.00 + x = 1.35 + 0.15
x = 1.35 + 0.15

Combine like terms: 1.35 + 0.15 = 1.5
x = 1.5

Simplifying
x = 1.5

Subproblem 2
x + -0.15 = -1.35

Simplifying
x + -0.15 = -1.35

Reorder the terms:
-0.15 + x = -1.35

Solving
-0.15 + x = -1.35

Solving for variable 'x'.

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

Add '0.15' to each side of the equation.
-0.15 + 0.15 + x = -1.35 + 0.15

Combine like terms: -0.15 + 0.15 = 0.00
0.00 + x = -1.35 + 0.15
x = -1.35 + 0.15

Combine like terms: -1.35 + 0.15 = -1.2
x = -1.2

Simplifying
x = -1.2

Solution
The solution to the problem is based on the solutions
from the subproblems.
x = {1.5, -1.2}