1. Let's begin by identifying what "step 20" involves in the previous solution. Since you asked for an explanation specifically of step 20, we need to clarify the context of this step. 2. Step 20 usually represents a particular part of a multi-step solution where a key operation such as simplification, substitution, or solving an equation happens. 3. Without the original problem's full content here, I will outline a typical explanation approach for a generic Step 20 that often involves simplifying or evaluating an expression. 4. Suppose in step 20, we simplified an expression like $$\frac{5x^2 - 15}{10x}$$ to $$\frac{5(x^2 - 3)}{10x} = \frac{x^2 - 3}{2x}$$. 5. The explanation is: we factored out the greatest common factor (GCF) 5 from the numerator and then divided both numerator and denominator by 5, reducing the fraction. 6. This step aims to simplify the expression so subsequent steps are easier to work with. 7. If you provide the exact content of step 20, I can give a detailed line-by-line explanation tailored to that. 8. Please share or restate step 20, and I'll be happy to clarify it in detail for you!