Question 993688
1188>-12t^2+240t
-12t^2+240t-1188<0
-t^2+20t-99<0
t^2-20t+99>0
(t-11)(t-9).0
at t>9 and <11 seconds.
at 9 seconds, -972+2160=1188
at 11 seconds, -1452+2640=1188

{{{graph(300,200,-10,15,-50,1500,-12x^2+240x)}}}