Answer: 9 miles per hour.
Step-by-step explanation:
In 1 hour they would run (1 4/5)/(1/5) = (9/5)*5 = 9 hours. So, they are running 9 miles per hour.
Answer:
-15/2
Step-by-step explanation:
The next step would be to distribute the negative two through the parenthesis,
-2n-6=9
then you add the six, -2n= 15
then you divide by 15 by negative 2 and get -15/2
Answer:32.1428571429 feet
Step-by-step explanation:
The flag is 15 feet.
It's shadow is 10.5 feet.
15/10.5=1.4285714286.
So the flag is above mentioned times of the shadow.
And the tree's hight will be,
22.5*1.4285714286
=32.1428571429 feet.
Answer:
(B)15,36,39
Step-by-step explanation:
To determine which of the line segments could create a Right Triangle, we check if it satisfies the Pythagoras Theorem, taking the longest part to be the Hypotenuse in all cases.
By Pythagoras Theorem: 
In 15,30,35

In 15,36,39

In 15, 20, 29

In 5,15,30

We can see that only 15,36,39 satisfies the required condition and thus it could be used to create a right triangle.