Answer:
h_max = 12.56 units
(the exercise does no specify the units)
Step-by-step explanation:
You have the following function:
[tex]h(t)=-16t^2+6t+12[/tex] (1)
To calculate the maximum height reach by you, you first derivative the function h(t) respect to t:
[tex]\frac{dh(t)}{dt}=-32t+6[/tex]
Next, you equal the result of the derivative to zero and you obtain t:
[tex]-32t+6=0\\\\t=\frac{6}{32}=\frac{3}{16}[/tex]
Then, you replace this value of t in the equation (1) and you obtain the maximum height:
[tex]h(t)=-16(\frac{3}{16})^2+6(\frac{3}{16})+12[/tex]
[tex]h(t)=12.56[/tex]
hence, the maximum height is 12.56 units