Question

Решите примеры 12 столбик(12,12,13)​

Answer 1

$-\frac{2}{7} *3,5-10,5*\frac{2}{7} =-\frac{2*3,5}{7} -\frac{10,5*2}{7} =-\frac{7}{7}-\frac{21}{7}=-\frac{28}{7}=-4$

$\frac{7}{9}x +\frac{11}{12}=\frac{13}{18} \\\\\frac{7}{9}x=\frac{13}{18}-\frac{11}{12} \\\\\frac{28}{36}x=\frac{26}{36}-\frac{33}{36}\\\\\frac{28}{36}x=-\frac{7}{36} \\\\x=-\frac{7}{36}:\frac{28}{36} \\\\ x=-\frac{7}{36}*\frac{36}{28}\\\\x=-\frac{1}{1}*\frac{1}{4}\\\\x=-\frac{1}{4} \\\\x=-0,25$