(8a2 – 3a – 3) – (5a2 + 2a – 10) = 8a2 – 3a – 3 – 5a2 – 2a + 10 = 8a2 – 5a2 – 3a – 2a – 3 + 10 = 3a2 – 5a + 7.
Ответ: 3a2 – 5a + 7