Решебник по математике 5 класс Алышева Нахождение неизвестного слагаемого Задание 2

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

\[20 + x = 50\]

\[x = 50 - 20\]

\[x = 30.\]

\[Проверка.\]

\[20 + 30 = 50\]

\[50 = 50.\]

\[2 + x = 50\]

\[x = 50 - 2\]

\[x = 48.\]

\[Проверка.\]

\[2 + 48 = 50\]

\[50 = 50.\]

\[x + 40 = 70\]

\[x = 70 - 40\]

\[x = 30.\]

\[Проверка.\]

\[30 + 40 = 70\]

\[70 = 70.\]

\[x + 4 = 70\]

\[x = 70 - 4\]

\[x = 66.\]

\[Проверка.\]

\[66 + 4 = 70\]

\[70 = 70.\]

\[60 + x = 100\]

\[x = 100 - 60\]

\[x = 40.\]

\[Проверка.\]

\[60 + 40 = 100\]

\[100 = 100.\]

\[x + 6 = 100\]

\[x = 100 - 6\]

\[x = 94.\]

\[Проверка.\]

\[94 + 6 = 100\]

\[100 = 100.\]