-3.6=r(-6r+0.6)

Solution for -3.6=r(-6r+0.6) equation:

Simplifying
-3.6 = r(-6r + 0.6)

Reorder the terms:
-3.6 = r(0.6 + -6r)
-3.6 = (0.6 * r + -6r * r)
-3.6 = (0.6r + -6r2)

Solving
-3.6 = 0.6r + -6r2

Solving for variable 'r'.

Reorder the terms:
-3.6 + -0.6r + 6r2 = 0.6r + -0.6r + -6r2 + 6r2

Combine like terms: 0.6r + -0.6r = 0.0
-3.6 + -0.6r + 6r2 = 0.0 + -6r2 + 6r2
-3.6 + -0.6r + 6r2 = -6r2 + 6r2

Combine like terms: -6r2 + 6r2 = 0
-3.6 + -0.6r + 6r2 = 0

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

Divide each side by '6'.
-0.6 + -0.1r + r2 = 0

Move the constant term to the right:

Add '0.6' to each side of the equation.
-0.6 + -0.1r + 0.6 + r2 = 0 + 0.6

Reorder the terms:
-0.6 + 0.6 + -0.1r + r2 = 0 + 0.6

Combine like terms: -0.6 + 0.6 = 0.0
0.0 + -0.1r + r2 = 0 + 0.6
-0.1r + r2 = 0 + 0.6

Combine like terms: 0 + 0.6 = 0.6
-0.1r + r2 = 0.6

The r term is -0.1r.  Take half its coefficient (-0.05).
Square it (0.0025) and add it to both sides.

Add '0.0025' to each side of the equation.
-0.1r + 0.0025 + r2 = 0.6 + 0.0025

Reorder the terms:
0.0025 + -0.1r + r2 = 0.6 + 0.0025

Combine like terms: 0.6 + 0.0025 = 0.6025
0.0025 + -0.1r + r2 = 0.6025

Factor a perfect square on the left side:
(r + -0.05)(r + -0.05) = 0.6025

Calculate the square root of the right side: 0.776208735

Break this problem into two subproblems by setting 
(r + -0.05) equal to 0.776208735 and -0.776208735.

Subproblem 1
r + -0.05 = 0.776208735

Simplifying
r + -0.05 = 0.776208735

Reorder the terms:
-0.05 + r = 0.776208735

Solving
-0.05 + r = 0.776208735

Solving for variable 'r'.

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

Add '0.05' to each side of the equation.
-0.05 + 0.05 + r = 0.776208735 + 0.05

Combine like terms: -0.05 + 0.05 = 0.00
0.00 + r = 0.776208735 + 0.05
r = 0.776208735 + 0.05

Combine like terms: 0.776208735 + 0.05 = 0.826208735
r = 0.826208735

Simplifying
r = 0.826208735

Subproblem 2
r + -0.05 = -0.776208735

Simplifying
r + -0.05 = -0.776208735

Reorder the terms:
-0.05 + r = -0.776208735

Solving
-0.05 + r = -0.776208735

Solving for variable 'r'.

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

Add '0.05' to each side of the equation.
-0.05 + 0.05 + r = -0.776208735 + 0.05

Combine like terms: -0.05 + 0.05 = 0.00
0.00 + r = -0.776208735 + 0.05
r = -0.776208735 + 0.05

Combine like terms: -0.776208735 + 0.05 = -0.726208735
r = -0.726208735

Simplifying
r = -0.726208735

Solution
The solution to the problem is based on the solutions
from the subproblems.
r = {0.826208735, -0.726208735}