Question

65 баллов. Срочно! Обчисліть значення виразу

Answer 1

Ответ:

$\frac{ {c}^{2} - 5c + cx - 5x }{ {c}^{2} + 5c + cx + 5x} \div \frac{2c - 10}{6c + 30} = \\ = \frac{c(c - 5) + x(c - 5)}{c(c + 5)+ x(c + 5)} \times \frac{6(c + 5)}{2(c - 5)} = \\ = \frac{(c - 5)(c + x)}{(c + 5)(c + x)} \times \frac{6(c + 5)}{2(c - 5)} = 3$

Answer 2

$\displaystyle\bf\\\frac{c^{2} -5c+cx-5x}{c^{2}+5c+cx+5x } :\frac{2c-10}{6c+30} =\frac{(c^{2} -5c)+(cx-5x)}{(c^{2}+5c)+(cx+5x) } :\frac{2\cdot(c-5)}{6\cdot(c+5)} =\\\\\\=\frac{c\cdot(c-5)+x\cdot (c-5)}{c\cdot(c+5)+x\cdot(c+5)} \cdot\frac{3\cdot(c+5)}{c-5} =\\\\\\=\frac{(c-5)\cdot(c+x)}{(c+5)\cdot(c+x)} \cdot\frac{3\cdot(c+5)}{c-5} =3$