Solution:
1. Start with the given equation: \frac{2}{3}b + 8 = -20
2. Subtract 8 from both sides to isolate the fraction involving b:
\frac{2}{3}b = -20 - 8
\frac{2}{3}b = -28
3. Multiply both sides of the equation by the reciprocal of the fraction \frac{2}{3} which is \frac{3}{2}:
b = -28 \cdot \frac{3}{2}
4. Simplify the right-hand side:
b = -28 \cdot 1.5
b = -42