Answer:
r = h + m
Step-by-step explanation:
h = r - m
Switch sides.
r - m = h
Add m to both sides.
r - m + m = h + m
Simplify the left side. -m + m = 0
r = h + m
Answer
Find out the how long did they rest in 8 hours.
To prove
As given
contestants in a dance-a-thon rest for the same amount of time every hour.
A couple rests for 25 minutes in 5 hours .
As
25 mintues = 5 hours

1 hours = 5 mintues
Thus in 1hours a the dance -a-thon rest for 5 mintues.
Now for 8 hours.
8 hours = 8 × 5 mintues
= 40 mintues
Therefore in 8 hours a dance-a-thon rest for 40 mintues.
Think, if something waves up and down at a certain rate, then its slope also will be changing with it along this wave at the same rate. If a function is periodic, with period c, then so is its derivative. I hope that this is the answer that you were looking for and it has helped you.
7 units between -12 and -5