2(a-1)+3.6=4.2

Solution for 2(a-1)+3.6=4.2 equation:

Simplifying
2(a + -1) + 3.6 = 4.2

Reorder the terms:
2(-1 + a) + 3.6 = 4.2
(-1 * 2 + a * 2) + 3.6 = 4.2
(-2 + 2a) + 3.6 = 4.2

Reorder the terms:
-2 + 3.6 + 2a = 4.2

Combine like terms: -2 + 3.6 = 1.6
1.6 + 2a = 4.2

Solving
1.6 + 2a = 4.2

Solving for variable 'a'.

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

Add '-1.6' to each side of the equation.
1.6 + -1.6 + 2a = 4.2 + -1.6

Combine like terms: 1.6 + -1.6 = 0.0
0.0 + 2a = 4.2 + -1.6
2a = 4.2 + -1.6

Combine like terms: 4.2 + -1.6 = 2.6
2a = 2.6

Divide each side by '2'.
a = 1.3

Simplifying
a = 1.3