Algebra Question *question in desc*

Question

A person standing at the edge of a cliff 48 feet tall throws a ball up and just off the cliff with an initial upward velocity of 8 feet per second. What is the maximum height of the ball? When did the ball hit the ground?

Answer 1

h(t) = -16t² + 8t + 48

 

Maximum height occurs at the vertex of the height-vs.-time parabola, which is at

 

t = -8/[2(-16)] sec = ? sec

 

Evaluate h(t) at this value of t to to get h_max.  To find when the ball hits the ground, set

 

h(t) = 0

 

and solve the resulting quadratic equation for t.  You will get a negative and a positive solution.  Since time starts at t = 0, discard the negative solution.