(5a-10)^2-(3a-8)^2+132a при a=-6

Question

(5a-10)^2-(3a-8)^2+132a при a=-6

Answer 1

25a^2 - 100a + 100 - (9a^2 - 48a + 64) + 132a = 
= 25a^2 - 100a + 100 - 9a^2 + 48a - 64 + 132a = 
= 16a^2 + 80a + 36 

a = - 6
16 ( - 6)^2  +80(-6) + 36 = 16*36 - 480 + 36 = 132