Answer:
17.08
Step-by-step explanation:
When it reaches its maximum, suppose that y = 0
Therefore you will need to factorise and solve
-16x^2 + 267 x + 107 = 0
Here you can use the quadratic equation
Where you will get x = -0.39 seconds or 17.08 seconds (rounded to 2 decimal places according to the question
Because -0.39 is negative, this answer can be deleted
Leacing x = 17.08 seconds