21. When Mary and Jack bought their house, their property taxes were $3,630 annually. After 8 years, their property taxes are now $4,065.60. What percent increase is this?

The height of a flare fired from the deck of a ship in distress can be modeled by h(t)= -2(8t^2-52t-28), where h is the height of the flare above water and t is the time in seconds. a. find the time it takes the flare to hit the water.

Ithink i know it but i want to be sure so can you me out ?

Find the axis of symmerty for x y=x squared -4x-8