Решебник по алгебре 7 класс Мерзляк ФГОС Задание 362

 

\[\boxed{\text{362\ (362).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]

\[1)\ 0,4x \cdot (5x - 6) + 7,2 =\]

\[= 2x \cdot (x + 0,6)\]

\[- 3,6x = - 7,2\]

\[x = 2.\]

\[Ответ:x = 2.\]

\[2)\ x \cdot (3x + 2) - 9 \cdot \left( x^{2} - 7x \right) =\]

\[= 6x \cdot (10 - x)\]

\[5x = 0\]

\[x = 0\]

\[Ответ:x = 0.\]

\[5x = 30\]

\[x = 6.\]

\[Ответ:x = 6.\ \]

\[\boxed{\text{362.}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]

\[1)*\ \cdot 3b^{4} = 12b^{6}\]

\[*\ = 12b^{6}\ :3b^{4}\]

\[*\ = 4b^{2}.\]

\[2) - 5a^{5}b^{2} \cdot \ *\ = - 20\ a^{6}b^{8}\]

\[*\ = - 20a^{6}b^{8}\ :\left( - 5a^{5}b^{2} \right)\]

\[*\ = 4\ ab^{6}.\]

\[3) - 7a^{3}b^{9} \cdot \ *\ = 4,2a^{5}b^{12}\]

\[*\ = 4,2a^{5}b^{12}\ :\left( - 7a^{3}b^{9} \right)\]

\[*\ = \ - 0,6a^{2}b^{3}.\]

\[4)\ 23a^{12}b^{16} \cdot \ *\ = - 23a^{29}b^{17}\]

\[*\ = - 23a^{29}b^{17}\ :23a^{12}b^{16}\]

\[*\ = - a^{17}\text{b.}\]