(1.1a+1.2b)+(2a-0.8b)=

Solution for (1.1a+1.2b)+(2a-0.8b)= equation:

Simplifying
(1.1a + 1.2b) + (2a + -0.8b) = 0

Remove parenthesis around (1.1a + 1.2b)
1.1a + 1.2b + (2a + -0.8b) = 0

Remove parenthesis around (2a + -0.8b)
1.1a + 1.2b + 2a + -0.8b = 0

Reorder the terms:
1.1a + 2a + 1.2b + -0.8b = 0

Combine like terms: 1.1a + 2a = 3.1a
3.1a + 1.2b + -0.8b = 0

Combine like terms: 1.2b + -0.8b = 0.4b
3.1a + 0.4b = 0

Solving
3.1a + 0.4b = 0

Solving for variable 'a'.

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

Add '-0.4b' to each side of the equation.
3.1a + 0.4b + -0.4b = 0 + -0.4b

Combine like terms: 0.4b + -0.4b = 0.0
3.1a + 0.0 = 0 + -0.4b
3.1a = 0 + -0.4b
Remove the zero:
3.1a = -0.4b

Divide each side by '3.1'.
a = -0.1290322581b

Simplifying
a = -0.1290322581b