**a) (y – 4)(y + 6)**
\[(y - 4)(y + 6) = y^2 + 6y - 4y - 24 = y^2 + 2y - 24\]
**б) (4a + 1)(2a - 3)**
\[(4a + 1)(2a - 3) = 8a^2 - 12a + 2a - 3 = 8a^2 - 10a - 3\]
**в) (2y - b)(4y + 3b)**
\[(2y - b)(4y + 3b) = 8y^2 + 6by - 4by - 3b^2 = 8y^2 + 2by - 3b^2\]
**г) (a - 3)(a² - 5a + 10)**
\[(a - 3)(a^2 - 5a + 10) = a^3 - 5a^2 + 10a - 3a^2 + 15a - 30 = a^3 - 8a^2 + 25a - 30\]