After t seconds, a ball in the air from the ground level reaches a height of h feet given by the equation h= 144t-16t^2 . After how many seconds will the ball hit the ground before rebounding?
h=0 Therefore: 144t-16t²=0 t (144-16t)=0 We have two equations: 1) t=0 (when the ball is released) 2) 144-16t=0 -16t=-144 t=-144 / -16=9 (this is the time )
