we need a better explaination
Answer:
(a) 
(b) 4 miles
Step-by-step explanation:
Given:
The sequence of run is an arithmetic sequence.
Miles traveled on day 1 = 1 mile
Miles traveled on day 7 = 2 miles
(a).
Explicit formula for an arithmetic sequence is given as:

Here, 
So,

Therefore, the explicit definition of the above sequence is given as:

Where,
is the miles covered on
day.
(b)
In order to find the distance covered by her on day 19, we plug in 19 for n in the above formula. This gives,

Therefore, the number of miles covered by her on day 19 is 4 miles.
Answer:
2z(4z^2+1)(2z+1)(2z-1)
Step-by-step explanation:
here is just some basic polynomial factoring where you find something both the numbers have in common and you take that out of the equation. here i just went a little bit deeper and after taking out the common factor i also expanded my answer further as this would be the fully correct answer.
hope this helps!
Rewrite 7/8 as a decimal by dividing 7 by 8:
7/8 = 0.875
Now to find how much further she has to run subtract where is now from the total distance:
0.875 - 0.3 = 0.575
She needs to run 0.575 miles more