## Algebra and Trigonometry 10th Edition

-1/2, $x\ne5$
Expression : $\frac{x-5}{10-2x} = \frac{-(5-x)}{2(5-x)} = \frac{-1}{2}$ with x≠5 as x=5 would make the denominator in the original expression zero and division by 0 is not allowed.