Question

помогите решит уровнение ​

Answer 1

$\displaystyle \tt 1). \ \ \frac{18}{x}-\frac{46}{x-5}=1\\\\{} \ \ \ \ \ \ 18\cdot(x-5)-46x=x^{2}-5x\\\\{} \ \ \ \ \ \ x^{2}+23x+90=0 \ \ \ \ \ \ \ D=b^{2}-4ac=169=13^{2}\\\\{} \ \ \ \ \ \ x_{1,2}=\frac{-bб\sqrt{D}}{2a}\\\\{} \ \ \ \ \ \ x_{1}=-5\\\\{} \ \ \ \ \ \ x_{2}=-18$

Ответ: {-5; -18}

$\displaystyle \tt 2). \ \ \left \{ {{7x-y=5} \atop {xy=18 \ \ \ }} \right. \ \ <=> \ \ \left \{ {{y=7x-5 \ \ \ \ \ } \atop {x(7x-5)=18}} \right.\\\\\\{}\ \ \ \ \ \ \ 7x^{2}-5x-18=0 \ \ \ \ \ \ \ D=b^{2}-4ac=25+504=529=23^{2}\\\\{} \ \ \ \ \ \ \ x_{1,2}=\frac{-bб\sqrt{D}}{2a}\\\\{} \ \ \ \ \ \ \ x_{1}=2 \ \ \ \ \ \ \ \ \ \ \ \ y_{1}=9\\\\{} \ \ \ \ \ \ \ x_{2}=-1\frac{2}{7} \ \ \ \ \ \ \ y_{2}=-14$

Ответ: {2; 9}, {-1 2/7; -14}