Perform the indicated operation. Simplify if possible. \( \frac{x^{2}}{x-9}-\frac{20 x-99}{x-9} \) The difference is \( \square \).

To perform the operation \( \frac{x^{2}}{x-9}-\frac{20 x-99}{x-9} \), we can combine the two fractions since they have a common denominator: \[ \frac{x^{2} - (20x - 99)}{x - 9} \] Next, simplify the numerator: \[ x^{2} - 20x + 99 = x^{2} - 20x + 99 \] Now, we can write the combined expression as: \[ \frac{x^{2} - 20x + 99}{x - 9} \] To simplify further, we can try factoring the numerator. We look for two numbers that multiply to \( 99 \) and add to \( -20 \). The numbers \( -11 \) and \( -9 \) fit, thus we factor: \[ x^{2} - 20x + 99 = (x - 11)(x - 9) \] Now substitute back into the fraction: \[ \frac{(x - 11)(x - 9)}{x - 9} \] Since \( x - 9 \) in the numerator and denominator cancels out (as long as \( x \neq 9 \)): \[ x - 11 \] So, the difference is \( x - 11 \).