Question

A ball is thrown into the air with an upward velocity of 80 feet per second. The function
h = -16t^2 + 80t models the height h, in feet, of the ball at time t, in seconds. When will the ball reach the ground?

after 3 seconds

after 4 seconds

after 5 seconds

after 6 seconds

Answer 1

Answer:

The ball will take 5 seconds to reach the ground

Step-by-step explanation:

Given:

$h=-16t^2+80t$

when the ball reaches the ground, h=0

$\implies\:-16t^2+80t=0$

$\implies\:16t^2=80t$

$\implies\:16t^2-80t=0$

$\implies\:16t(t-5)=0$

$\implies\:t=0,5$

As per data t=0 is not applicaple

Therefore t = 5 seconds