Answer:
A good way to know how to solve a problem like this is to look at the units. Here we have miles per hour (65 miles/hour) and hours (5 hours) and we want to find X miles. So take a look at the units:
(Miles/hour) * (hours) = miles
So we can just plug in the values…
65 * 5 = 325
Whenever I get confused by a question like this I always try to remember that the word "per" just means divided by. So mph = miles/hour. And from there the algebra is pretty simple.
Another tip, your physics professor will always be tickled if at the end of your answer you list some of the assumptions you made like this: "assuming the car is traveling at a perfectly constant rate without stopping."
Answer:
The slope of the line is y = 1.8x
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
There's an app called photomath that would be useful for these kinds of problems!