(2a + 5)^2 - 3(a - 7) + 9a^2 - 79
Expanding the first term:(2a + 5)(2a + 5)= 4a^2 + 10a + 10a + 25= 4a^2 + 20a + 25
Expanding the second term:3(a - 7)= 3a - 21
Therefore, the expression simplifies to:4a^2 + 20a + 25 - 3a + 21 + 9a^2 - 79= 13a^2 + 17a - 33
(2a + 5)^2 - 3(a - 7) + 9a^2 - 79
Expanding the first term:
(2a + 5)(2a + 5)
= 4a^2 + 10a + 10a + 25
= 4a^2 + 20a + 25
Expanding the second term:
3(a - 7)
= 3a - 21
Therefore, the expression simplifies to:
4a^2 + 20a + 25 - 3a + 21 + 9a^2 - 79
= 13a^2 + 17a - 33