Решите уравнение: 7+3(-k-3(k+5))=5(7-2k)+k.

Ответ:

\[7 + 3 \cdot \left( - k - 3 \cdot (k + 5) \right) =\]

\[= 5 \cdot (7 - 2k) + k\]

\[7 + 3 \cdot ( - k - 3k - 15) =\]

\[= 35 - 10k + k\]

\[7 - 3k - 9k - 45 - 35 + 10k - k = 0\]

\[- 3k - 73 = 0\]

\[3k = - 73\]

\[k = - \frac{73}{3}\]

\[k = - 24\frac{1}{3}.\]

\[Ответ:k = - 24\frac{1}{3}.\]