What is the solution set for the quadratic equation x squared - 16 equals 0

Aquantity with an initial value of 3900 decays exponentially at a rate of 35% every hour. what is the value of the quantity after 0.5 days, to the nearest hundredth?

East black horse $0.25 total budget is $555 it'll cost $115 for other supplies about how many flyers do you think we can buy

With number 11 ( show how you got the answer)