0.3[r+2]=-0.1[2r-4]

Solution for 0.3[r+2]=-0.1[2r-4] equation:

Simplifying
0.3[r + 2] = -0.1[2r + -4]

Reorder the terms:
0.3[2 + r] = -0.1[2r + -4]
[2 * 0.3 + r * 0.3] = -0.1[2r + -4]
[0.6 + 0.3r] = -0.1[2r + -4]

Reorder the terms:
0.6 + 0.3r = -0.1[-4 + 2r]
0.6 + 0.3r = [-4 * -0.1 + 2r * -0.1]
0.6 + 0.3r = [0.4 + -0.2r]

Solving
0.6 + 0.3r = 0.4 + -0.2r

Solving for variable 'r'.

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

Add '0.2r' to each side of the equation.
0.6 + 0.3r + 0.2r = 0.4 + -0.2r + 0.2r

Combine like terms: 0.3r + 0.2r = 0.5r
0.6 + 0.5r = 0.4 + -0.2r + 0.2r

Combine like terms: -0.2r + 0.2r = 0.0
0.6 + 0.5r = 0.4 + 0.0
0.6 + 0.5r = 0.4

Add '-0.6' to each side of the equation.
0.6 + -0.6 + 0.5r = 0.4 + -0.6

Combine like terms: 0.6 + -0.6 = 0.0
0.0 + 0.5r = 0.4 + -0.6
0.5r = 0.4 + -0.6

Combine like terms: 0.4 + -0.6 = -0.2
0.5r = -0.2

Divide each side by '0.5'.
r = -0.4

Simplifying
r = -0.4