Question

Find the sum and express it in simplest form.

(3t2 + 6t + 1) + (-9t2 - 5t + 5)

Answer 1

Hello and Welcome to OpenStudy :)
when such two parenthesis are connected by addition, they can be taken out without consequence, so you can get something like
3t^2 + 6t + 1 - 9t^2 - 5t + 5
then you can add/subtract "like terms"
as in terms of the same power
for example 4t^2 + 5t^2 = 9t^2
but 4t^2 + 5t cannot be added