Answer:
as shown
Step-by-step explanation:
d = -16t^2+124t d= 225 feet
225 = -16t^2 +124 t
225 = -16(t^2 -7.75t))
do that perfect square thing 7.75/2 squared... =15.015625
225 = -16 ( t^2 - 7.75t +15.015625) +(16)(- 15.015625)
225 = -16 ( t-15.015625)^2 -240.25
465.25 = -16 (t -15.015625)^2
29.078 =(t -15.015625)^2
5.39 =t -15.015625
20.405625 = t
in seconds of course
:)