we need to multiply both sides by a number let us cancel the denominators
So 3 * 2 = 6
Multiply both sides by the factor 6
6/2 = 3 and 6/3 = 2, then
3(b + 13) = 2(-5b)
Let us simplify each side
3(b) + 3(13) = -10b
3b + 39 = -10b
let us collect b on the left side and the number on the other side
3b + 10b = -39
13b = -39
Divide both sides by 13 to find b
b = -3