6-(-b)=-0.4

Solution for 6-(-b)=-0.4 equation:

Simplifying
6 + -1(-1b) = -0.4

Remove parenthesis around (-1b)
6 + -1 * -1b = -0.4

Multiply -1 * -1
6 + 1b = -0.4

Solving
6 + 1b = -0.4

Solving for variable 'b'.

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

Add '-6' to each side of the equation.
6 + -6 + 1b = -0.4 + -6

Combine like terms: 6 + -6 = 0
0 + 1b = -0.4 + -6
1b = -0.4 + -6

Combine like terms: -0.4 + -6 = -6.4
1b = -6.4

Divide each side by '1'.
b = -6.4

Simplifying
b = -6.4