ASAP Which set of expressions are not equivalent?

3(3a) + a(3 a) and 3 a2 + 9 a
5(3 x) - 4(3 x) and 3 x
4(3 a) - 2(4 a) and 4 a2
4 x( x) + 3(2 x) and 4 x2 + 6 x

After reading 80% of her e-mails in her inbox, danette still has m unread e-mails. which of the following expressions could represent the number of e-mails danette had in her inbox before she started reading? choose 2 answers: (choice a) 5m (choice b) 1.8m (choice c) 80m (choice d) m/0.8 (choice e) m/1−0.8