Problema Solution
A basketball bounces off the ground. The ball height y (in feet) after t seconds can be modeled by y = -16t +20t
How many seconds is the basketball in the air?
Answer provided by our tutors
-16t^2+20t=0.
-4t(4t-5)=0.
t=0, t=5/4.
Negelct t=0 .
t=5/4=1.25sec.
The ball will be in air for 1.25 sec.