Use mental math to find the sum 542+54

To determine the number of deer in a forest a forest ranger tags 280 and releases them back

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.

How do you determine if an ordered pair is a solution to a given equation?