To simplify the expression \( x^2 - 497x - x^2 \), we first observe that the \( x^2 \) terms cancel each other out:
\[ x^2 - x^2 - 497x = -497x \]
Thus, the expression simplifies directly to:
\[ -497x \]
Now let's review the provided responses:
- \( x + 7x \) -- This simplifies to \( 8x \), which is incorrect.
- \( \frac{x + 7}{x} \) -- This form does not match the simplified expression.
- \( -7 \) -- This is incorrect as it does not relate to our expression.
- \( -\frac{(x + 7)}{x} \) -- This also does not match the simplified expression.
- \( -7x \) -- This is incorrect; the coefficient is \(-497\).
None of the provided responses match the correct simplified expression of \(-497x\).