B-3/15=1

I have a lot of answers but I don't know which one is correct

b-3/15=-1

We simplify the equation to the form, which is simple to understand

b-3/15=-1

Simplifying:

b-0.2=-1

We move all terms containing b to the left and all other terms to the right.

+1b=-1 + 0.2

We simplify left and right side of the equation.

+1b=-0.8

We divide both sides of the equation by 1 to get b.

b=-0.8