If an object is propelled upward from a height of s feet at an initial veloc ity of v feet per second, then its height h after t seconds is given by the equation h = - 16^2+vt+s, where h is in feet. If the object is propelled from a height of 12 feet with an initial velocity of 96 feet per second its height h is given by the equation h = - 16t^2 + 96t+12. After how many seconds is the height 120 feet?

Question

Mathematics

Alyvia Moss

2 November, 06:36

If an object is propelled upward from a height of s feet at an initial veloc ity of v feet per second, then its height h after t seconds is given by the equation h = - 16^2+vt+s, where h is in feet. If the object is propelled from a height of 12 feet with an initial velocity of 96 feet per second its height h is given by the equation h = - 16t^2 + 96t+12. After how many seconds is the height 120 feet?

+1

Answers (1)

Know the Answer?

Tripp · Answer 1

That would be obtained by substituting h = 120 and solving : -

-16t^2 + 96t + 12 = 120

-16T^2 + 96t - 108 = 0

solving gives t = 1.5 and t = 4.5

so after propulsion it takes 1.5 seconds to reach 120 feet.