Номер 57 гдз 8 класс алгебра Муравин Муравина

а)\begin{equation} \frac{a}{b}\cdot \frac{b}{5} \end{equation} \begin{equation}\frac{a\cdot b}{b\cdot 5}=\frac{a}{5} \end{equation} б) \begin{equation}\frac{x}{8}\cdot \frac{8}{y} \end{equation} \begin{equation}\frac{8x}{8y}=\frac{x}{y} \end{equation} в) \begin{equation}\frac{3a}{5}\cdot \frac{10b}{9} \end{equation} \begin{equation}\frac{3a\cdot 10b}{5\cdot 9}=\frac{2ab}{3} \end{equation} г)\begin{equation}\frac{14x}{9}\cdot \frac{3a}{35x} \end{equation} \begin{equation}\frac{14x\cdot 3a}{9\cdot 35x}=\frac{2a}{15} \end{equation} д)\begin{equation}8\cdot \frac{3}{4ab} \end{equation} \begin{equation}\frac{8\cdot 3}{4ab}=\frac{6}{ab} \end{equation} е)\begin{equation}\frac{7x}{5y}\cdot 15 \end{equation} \begin{equation}\frac{7x\cdot 15}{5y}=\frac{21x}{y} \end{equation} ж)\begin{equation}\frac{1}{3}x^{2}\cdot \frac{6}{25x} \end{equation} \begin{equation}\frac{x^{2}\cdot6 }{3\cdot 25x}=\frac{2x}{25} \end{equation} з)\begin{equation} -\frac{3}{8}a\cdot \frac{5a^{2}}{9} \end{equation} \begin{equation}-\frac{3a\cdot 5a^{2}}{8\cdot 9}=\frac{5a^{3}}{24} \end{equation} и) \begin{equation}\frac{50a^{2}x^{2}}{7\cdot y^{4}}\cdot \frac{14x^{2}}{75a^{3}y} \end{equation} \begin{equation}\frac{50a^{2}x^{2}\cdot 14x^{2}}{7y^{4}\cdot 75a^{3}y}=\frac{4x^{4}}{3y^{5}} \end{equation} к) \begin{equation}\frac{8a^{2}}{21x^{4}}\cdot 35ax^{3} \end{equation} \begin{equation}\frac{8\cdot a^{2}\cdot 35ax^{3}}{21x^{4}}=\frac{40a^{3}}{3x} \end{equation} л)\begin{equation}-0,9a^{2}c^{2}\cdot \frac{5a}{c^{3}} \end{equation} \begin{equation}-\frac{0,9a^{2}c^{2}\cdot 5a}{c^{3}}=-4,5\frac{a^{3}}{c} \end{equation} м)\begin{equation}-\frac{25b^{4}}{32n^{6}}\cdot \left ( -4bn \right )^{2} \end{equation} \begin{equation}-\frac{25b^{4}}{32n^{6}}\cdot 16b^{2}n^{2}= \end{equation} \begin{equation}=-\frac{25\cdot b^{4}\cdot 16b^{2}n^{2}}{32n^{6}}= \end{equation} \begin{equation}=-\frac{25b^{6}}{2n^{4}}=12,5\frac{b^{6}}{n^{4}} \end{equation}