4.6-(-b)=0.4

Solution for 4.6-(-b)=0.4 equation:

Simplifying
4.6 + -1(-1b) = 0.4

Remove parenthesis around (-1b)
4.6 + -1 * -1b = 0.4

Multiply -1 * -1
4.6 + 1b = 0.4

Solving
4.6 + 1b = 0.4

Solving for variable 'b'.

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

Add '-4.6' to each side of the equation.
4.6 + -4.6 + 1b = 0.4 + -4.6

Combine like terms: 4.6 + -4.6 = 0.0
0.0 + 1b = 0.4 + -4.6
1b = 0.4 + -4.6

Combine like terms: 0.4 + -4.6 = -4.2
1b = -4.2

Divide each side by '1'.
b = -4.2

Simplifying
b = -4.2