What is the starting amount , the decay rate , and equation for this problem ? “you bought a video game for $50 dollars, but it loses 25% of its value every six months . how much will the video game be worth after 2 years”

Determine whether the set of whole numbers is closed under addition. explain why the set is or is not closed. give an example.

1- what do you think the product of a nonzero rational number and an irrational number is? is it rational or irrational? make use of variables, the closure property of integers, and possibly a proof by contradiction to prove your hypothesis.2- why do we have to specify that the rational number must be nonzero when we determine what the product of a nonzero rational number and an irrational number is? if the rational number were 0, would it give us the same result we found in the first question?

Which of the following quartic functions has x = –1 and x = –2 as its only two real zeroes?