1. Let's first restate the problem or the context of the steps so far to ensure clarity. 2. Step 4 usually involves applying a key formula or simplifying an expression further. 3. For example, if step 4 involves solving an equation like $$ax+b=0$$, the rule is to isolate the variable by subtracting $b$ from both sides and then dividing by $a$. 4. This gives $$x=\frac{-b}{a}$$. 5. If step 4 involves factoring, remember to look for common factors or use formulas like difference of squares: $$a^2 - b^2 = (a-b)(a+b)$$. 6. If you provide the exact expression or step 4 content, I can explain the intermediate steps in detail. 7. The key is to break down each operation: what is done to both sides of the equation, how terms are combined or simplified, and why each step is valid. 8. Feel free to share the exact step 4 text or equation for a precise explanation.