Решебник по математике 2 класс Моро Часть 1, 2 Часть 2 | Страница 18

\[\boxed{Стр.\ \mathbf{18}\text{.\ \ }\mathbf{ОК\ ГДЗ\ - \ домашка\ на\ 5}}\]

\[\boxed{\mathbf{1}.}\]

\[7 + 73 = 80\]

\[80 - 7 = 73\]

\[80 - 73 = 7\]

\[7 + 73 = 80\]

\[80 - 73 = 7\]

\[80 - 7 = 73\]

\[4 + 56 = 60\]

\[60 - 4 = 56\]

\[60 - 56 = 4\]

\[9 + 81 = 90\]

\[81 + 9 = 90\]

\[90 - 81 = 9\]

\[\boxed{\mathbf{2}.}\]

\[1)\ 40 - 5 = 35\ (страниц) -\]

\[осталось\ прочитать.\]

\[2)\ 40 + 35 = 75\ (страниц) - в\ \]

\[книге.\]

\[Ответ:75\ страниц.\]

\[\boxed{\mathbf{3}.}\]

\[Первый\ способ.\]

\[(10 + 50) - 8 = 60 - 8 =\]

\[= 52\ (рубля).\]

\[Второй\ способ.\]

\[10 + (50 - 8) = 10 + 42 =\]

\[= 52\ рубля.\]

\[Третий\ способ.\]

\[50 + (10 - 8) = 50 + 2 =\]

\[= 52\ рубля.\]

\[Ответ:осталось\ 52\ рубля.\]

\[\boxed{\mathbf{4}.}\]

\[\boxed{\mathbf{5}.}\]

\[35 - (7 + 8) = 35 - 15 = 20\]

\[84 - 40 - 4 = 44 - 4 = 40\]

\[90 - 26 = 64\]

\[\boxed{\mathbf{6}.}\]

\[x - 9 = 4\]

\[x = 4 + 9\]

\[x = 13.\]

\[y + 7 = 15\]

\[y = 15 - 7\]

\[y = 8.\]

\[35 - x = 30\]

\[x = 35 - 30\]

\[x = 5.\]

\[\boxed{\mathbf{Вопрос}.}\]

\[63 - (5 + 8) = 63 - 13 = 50\]

\[68 - 20 + 2 = 48 + 2 = 50\]

\[80 - 32 = 48\]

\[\boxed{\mathbf{Задание\ на\ полях}.\ Ребусы}\]