Решебник по математике 5 класс Мерзляк ФГОС Задание 490

 

\[\boxed{\ \mathbf{490\ (490)}.\ Еуроки\ - \ ДЗ\ без\ мороки}\]

\[1)\ 8 \cdot (x - 14) = 56\]

\[x - 14 = 56\ :8\]

\[x - 14 = 7\]

\[x = 7 + 14\]

\[x = 21\]

\[Ответ:21.\]

\[2)\ (46 - x) \cdot 19 = 418\]

\[46 - x = 418\ :19\]

\[46 - x = 22\]

\[x = 46 - 22\]

\[x = 24\]

\[Ответ:24.\]

\[3)\ 9 \cdot (143 - 13x) = 234\]

\[143 - 13x = 234\ :9\]

\[143 - 13x = 26\]

\[13x = 143 - 26\]

\[13x = 117\]

\[x = 117\ :13\]

\[x = 9\]

\[Ответ:9.\]

\[4)\ 17 \cdot (5x - 16) = 238\]

\[5x - 16 = 238\ :17\]

\[5x - 16 = 14\]

\[5x = 14 + 16\]

\[5x = 30\]

\[x = 30\ :5\]

\[x = 6\]

\[Ответ:6.\]

\[\boxed{\ \mathbf{490.}}\]

\[1)\ 3^{2} + 4^{2} = 9 + 16 = 25\ \]

\[2)\ 3^{3} + 2^{3} = 27 + 8 = 35\ \]

\[3)\ 26^{2} - \left( 12^{2} \cdot 3 + 175 \right) =\]

\[= 676 - (144 \cdot 3 + 175) =\]

\[= 676 - (432 + 175) =\]

\[= 676 - 607 = 69\]

\[4)\ 6^{3} - 2 \cdot 4^{3} - 1^{3} =\]

\[= 36 \cdot 6 - 2 \cdot 16 \cdot 4 - 1 =\]

\[= 216 - 128 - 1 = 87\]

\[5)\ 15^{2}\ :\left( 13^{2} - 124 \right) =\]

\[= 225\ :(169 - 124) =\]

\[= 225\ :45 = 5\]

\[6)\ 8^{3}\ :\left( 4^{2} - 2^{3} \right) =\]

\[= 64 \cdot 8\ :(16 - 8) =\]

\[= 64 \cdot 8\ :8 = 64 \cdot 1 = 64\]