1. Let's clarify the origin of the term $8x^2$ in the expression. 2. Typically, $8x^2$ comes from multiplying constants and variables, for example, $4 \times 2x^2 = 8x^2$. 3. If you provide the original expression or equation, I can show exactly how $8x^2$ was derived step-by-step. 4. Without the original context, the general rule is that coefficients multiply and variables with the same base add exponents: $x^a \times x^b = x^{a+b}$. 5. So, if you had $4x \times 2x$, it becomes $4 \times 2 \times x^{1+1} = 8x^2$. 6. Please share the original problem for a precise explanation.