Question 816725
  <pre><font face = "Tohoma" size = 3 color = "indigo"><b> 
Hi,
An object is thrown upward from the top of a 144-foot building with and initial velocity of 128 feet per second.
 h = -16t^2+128t+144. when will the object hit the ground? when h = 0
 -16t^2+128t+144 = 0
  t^2 -8t - 9 = 0
 (t-9)(t+1) = 0,  t = 9sec
  
{{{drawing(300,300,   -.5,10,-20,400,  
 grid(1),
circle(0,144,.2),
graph( 300, 300, -.5,10,-20,400,0,-16x^2+128x+144))}}}