\[\boxed{\text{441\ (441).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
Пояснение.
Решение.
\[1)\ 2x \cdot (a + b) + y \cdot (a + b) =\]
\[= (a + b) \cdot (2x + y).\]
\[2)\ (a - 4) - b \cdot (a - 4) =\]
\[= (a - 4) \cdot (1 - b).\]
\[3)\ 5a \cdot (m - n) + 7b \cdot (m - n) =\]
\[= (m - n) \cdot (5a + 7b).\]
\[4)\ 6x \cdot (4x + 1) - 11 \cdot (4x + 1) =\]
\[= (4x + 1) \cdot (6x - 11).\]
\[5)\ a \cdot (c - d) + b \cdot (d - c) =\]
\[= (c - d) \cdot (a - b).\]
\[6)\ x \cdot (x - 6) - 10 \cdot (6 - x) =\]
\[= (x - 6) \cdot (x + 10).\]
\[7)\ b \cdot (b - 20) + (20 - b) =\]
\[= (b - 20) \cdot (b - 1).\]
\[8)\ 6a \cdot (a - 3b) - 13b \cdot (3b - a) =\]
\[= (a - 3b) \cdot (6a + 13b).\]
\[9)\ (m - 9)^{2} - 3 \cdot (m - 9) =\]
\[= (m - 9) \cdot (m - 9 - 3) =\]
\[= (m - 9) \cdot (m - 12).\]
\[10)\ a \cdot (a + 5)^{2} + (a + 5) =\]
\[= (a + 5) \cdot \left( a \cdot (a + 5) + 1 \right) =\]
\[= (a + 5) \cdot \left( a^{2} + 5a + 1 \right).\]
\[11)\ \left( m^{2} - 3 \right) - n \cdot \left( m^{2} - 3 \right)^{2} =\]
\[= \left( m^{2} - 3 \right) \cdot \left( 1 - n \cdot \left( m^{2} - 3 \right) \right) =\]
\[= \left( m^{2} - 3 \right) \cdot \left( 1 - nm^{2} + 3n \right).\]
\[= (p - 12) \cdot \left( 8c + 7d \cdot (p - 12) \right) =\]
\[= (p - 12) \cdot (8c + 7dp - 84d)\text{.\ }\]