\[\boxed{\mathbf{Проверочная\ работа\ №2.\ Вычитание}}\]
\[\boxed{\text{1.}}\]
\[- 15 - ( - 7) = - 15 + 7 = - 8.\]
\[\boxed{\text{2.}}\]
\[20 - 50 = - 30.\]
\[\boxed{\text{3.}}\]
\[x - ( - 5) = - 5\]
\[x + 5 = - 5\]
\[x = - 5 - 5\]
\[x = - 10.\]
\[Ответ:из\ ( - 10).\]
\[\boxed{\text{4.}}\]
\[- 7 - x = - 10\]
\[x = - 7 - ( - 10) = - 7 + 10\]
\[x = 3.\]
\[Ответ:число\ 3.\]
\[\boxed{\text{5.}}\]
\[- 12 + x = - 3\]
\[x = - 3 - ( - 12) = - 3 + 12\]
\[x = 9{^\circ}С - изменилась\ \]
\[температура.\]
\[Ответ:поднялась\ на\ 9{^\circ}С.\]
\[\boxed{\text{6.}}\]
\[Расстояние\ равно\ 10\ ед.\ отр:\]
\[6 - ( - 4) = 6 + 4 = 10.\]
\[\boxed{\text{7.}}\]
\[Да.\]
\[\boxed{\text{8.}}\]
\[Нет.\]