I've worked these problems but I was just wondering if someone could check over them to see if they're correct...if not please help!

Question

(u-2)(u+7)
my answer: 7u^2-49u

(5t-4)^2
my answer: 25t^2-40+16

Thank you :)

Answer 1

hmm, well use either FOIL or the distributive property. I will use distributive property:
(u-2)(u+7)
my answer: 7u^2-49u
-----------------------
u(u+7) -2(u+7)
u^2 + 7u - 2u - 14
=
u^2 + 5 u - 14
===============================

Answer 2

25t^2-40+16
You forgot a t
25t^2-40t+16