3[1.2b-1]+3.6=4.2

Solution for 3[1.2b-1]+3.6=4.2 equation:

Simplifying
3[1.2b + -1] + 3.6 = 4.2

Reorder the terms:
3[-1 + 1.2b] + 3.6 = 4.2
[-1 * 3 + 1.2b * 3] + 3.6 = 4.2
[-3 + 3.6b] + 3.6 = 4.2

Reorder the terms:
-3 + 3.6 + 3.6b = 4.2

Combine like terms: -3 + 3.6 = 0.6
0.6 + 3.6b = 4.2

Solving
0.6 + 3.6b = 4.2

Solving for variable 'b'.

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

Add '-0.6' to each side of the equation.
0.6 + -0.6 + 3.6b = 4.2 + -0.6

Combine like terms: 0.6 + -0.6 = 0.0
0.0 + 3.6b = 4.2 + -0.6
3.6b = 4.2 + -0.6

Combine like terms: 4.2 + -0.6 = 3.6
3.6b = 3.6

Divide each side by '3.6'.
b = 1

Simplifying
b = 1