Step-by-step explanation:
Simplifying
b + -0.2b = 0
Combine like terms: b + -0.2b = 0.8b
0.8b = 0
Solving
0.8b = 0
Solving for variable 'b'.
Move all terms containing b to the left, all other terms to the right.
Divide each side by '0.8'.
b = 0
Simplifying
b = 0