\[\boxed{\mathbf{Страница\ 55.\ }\mathbf{Еуроки\ - \ ДЗ\ без\ мороки}}\]
\[\boxed{\mathbf{1.\ }}\]
\[x + 7 = 7\]
\[x = 0\]
\[23 - y = 18\]
\[y = 5\]
\[60\ :n = 4\]
\[n = 15\]
\[k \cdot 3 = 54 + 36\]
\[k = 30\]
\[0;5;15;30;\mathbf{50;75;105}\mathbf{.}\]
\[\boxed{\mathbf{2.\ }}\]
\[\textbf{а)}\ (x + 3)\ :8 = 5\]
\[x + 3 = 5 \cdot 8\]
\[x + 3 = 40\]
\[x = 40 - 3\]
\[x = 37\]
\[Ответ:x = 37.\]
\[\textbf{б)}\ a\ :8 = 5\]
\[a = 5 \cdot 8\]
\[a = 40\]
\[x + 3 = 40\]
\[x = 40 - 3\]
\[x = 37\]
\[Уравнение\ а)\ состоит\ из\ двух\ \]
\[уравнений\ б):сначала\ мы\ \]
\[находим\ неизвестное\ делимое\ \]
\[(x + 3),\ а\ потом\ неизвестное\]
\[слагаемое\ (x).\]
\[\boxed{\mathbf{3.\ }}\]
\[\textbf{а)}\ x\ :9 + 8 = 12\]
\[x\ :9 = 12 - 8\]
\[x\ :9 = 4\]
\[x = 4 \cdot 9\]
\[x = 36\]
\[Ответ:x = 36.\]
\[\textbf{б)}\ 5 \cdot (15 - x) - 7 = 28\]
\[5 \cdot (15 - x) = 28 + 7\]
\[5 \cdot (15 - x) = 35\]
\[15 - x = 35\ :5\]
\[15 - x = 7\]
\[x = 15 - 7\]
\[x = 8\]
\[Ответ:x = 8.\ \]
\[\boxed{\mathbf{4.\ }}\]
\[72 + 8 - 35 = 45\]
\[62 - 20 + 7 = 49\]
\[54 - 9 - 20 = 25\]
\[\mathbf{Урок\ 37.\ Решение\ задач}\]