Aball is thrown in the air from a ledge. its height in feet is represented by f(x) = –16(x2 – 7x – 8), where x is the number of seconds since the ball has been thrown. the height of the ball is 0 feet when it hits the ground. how many seconds does it take the ball to reach the ground?

is the functions that determines the height of the ball in Feet, after x seconds being thrown.

so for example to calculate how many feet above the ground in the ball 5 seconds after being thrown, we calculate f(5)

feet

to solve our problem we need to find x such that f(x)=0

so we solve :





using the quadratic formula, le a=1, b=-7, c=-8



so 



, which cannot be the solution to our problem.

8 s

What class is this? i have no idea and i'm not going to give you the wrong answer. do you have a graph that goes with all the questions