Question

найдите значения выражения​

Answer 1

Ответ:

$\displaystyle (x - 9) \div \frac{ {x}^{2} - 18x + 81 }{x + 9} = (x - 9) \times \frac{x + 9}{x {}^{2} - 2 \times 9 \times x + 9 {}^{2} } = (x - 9) \times \frac{x + 9}{(x - 9) {}^{2} } = \frac{x + 9}{x - 9} = \frac{45 + 9}{45 - 9} = \frac{54}{36} = \frac{3}{2} = 1.5$