Answer:
The answer should be: r ≈ 8.21
Answer: 
<u>Step-by-step explanation:</u>
1st marble and 2nd marble

Answer:
The value of y is 
Step-by-step explanation:
we know that
A relationship between two variables, x, and y, represent a proportional variation if it can be expressed in the form
or
In a proportional relationship the constant of proportionality k is equal to the slope m of the line and the line passes through the origin
In this problem the line passes through the origin
therefore
Is a proportional variation
Find the value of k
with the point 

The equation is equal to

so
For 
substitute

Answer:
sqrt(20)
Step-by-step explanation:
The two perpendicular side lengths are equal, so using Pythagoras theorem:
x = sqrt( sqrt(10)^2 + sqrt(10)^2 )
x = sqrt(10 + 10)
x = sqrt(20)