Ok
y=-0.04x^2+8.3x+4.3
when the rocket reaches the ground (when height=0, ie when y=0), then the rocket will land, find the x coordinate
set y=0
0=-0.04x^2+8.3x+4.3
use quadratic formula
if you have ax^2+bx+c=0, then
x=

a=-0.04
b=8.3
c=4.3
x=

x=208.017 or -0.516785
xrepresents horizontal distance
you cannot have a negative horizontal distance unless you fired and theh wind blew it backwards
therefor x=280.017 is the answer
208.02 m
Answer: 41.5 min
Step-by-step explanation:
This problem can be solved with the Radioactive Half Life Formula:
(1)
Where:
is the final amount of the radioactive element
is the initial amount of the radioactive element
is the time elapsed
is the half life of the radioactive element
So, we need to substitute the given values and find
from (1):
(2)
(3)
(4)
Applying natural logarithm in both sides:
(5)
(6)
Clearing
:
This is the time elapsed
The eee part is the right part because I’m not trying to get points I’m so sorry