Question

( \frac{x}{x-1}-1 ) * \frac{xy-y}{x}

Answer 1

$( \frac{x}{x-1}-1 ) * \frac{xy-y}{x} = \\ \frac{x - x + 1}{x - 1} \times \frac{y(x - 1)}{x} = \\ = \frac{1}{x - 1} \times \frac{y(x - 1)}{x} = \\ = \frac{y}{x}$