Question

The function f(x) = –10(x)(x – 4) represents the approximate height of a projectile launched from the ground into the air with an initial velocity of 40 meters per second. How long, from launch to landing, does the projectile stay in the air?

Answer 1

4 seconds is how long, 100% correct just got it right on the quiz.

Answer 2

Hello,

f(x)=0
-10x(x-4)=0
x=0 or x=4

Launch : time 0
Landing,:time 4
Duration=4-0=4 (s)