Respuesta :

Answer:

Height after 5 seconds is 215 ft

Step-by-step explanation:

Given that:

The initial velocity of object which is projected upwards is 123 ft/sec.

Height of the object, h after time t in seconds,  is given as:

[tex]h=-16t^2+123t[/tex]

Here, t will always be positive, so [tex]123t[/tex] and [tex]16t^2[/tex] will also be positive.

But coefficient of [tex]16t^2[/tex] is negative, that means something is subtracted from the positive term [tex]123t[/tex].

To find:

Height of object after 5 seconds.

Solution:

Given that [tex]t=5[/tex] seconds.

Let us put the value in the given relation of [tex]h[/tex] and [tex]t[/tex]:

[tex]h=-16\times 5^2+123 \times 5\\\Rightarrow h=-400+615\\\Rightarrow \bold{h = 215\ ft}[/tex]

So, height after 5 seconds is 215 ft.