(-a)-(-5.7)=-1.2

Solution for (-a)-(-5.7)=-1.2 equation:

Simplifying
(-1a) + -1(-5.7) = -1.2

Multiply -1 * -5.7
(-1a) + 5.7 = -1.2

Reorder the terms:
5.7 + (-1a) = -1.2

Solving
5.7 + (-1a) = -1.2

Solving for variable 'a'.

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

Add '-5.7' to each side of the equation.
5.7 + -5.7 + (-1a) = -1.2 + -5.7

Combine like terms: 5.7 + -5.7 = 0.0
0.0 + (-1a) = -1.2 + -5.7
(-1a) = -1.2 + -5.7

Combine like terms: -1.2 + -5.7 = -6.9
(-1a) = -6.9

Divide each side by '-1'.
a = 6.9

Simplifying
a = 6.9