Solving for a variable in an equation means, we are changing the subject of formula of the equation.
The equation of r is: 
The equation is given as:

We start by multiplying both sides by 3

Rewrite as:

Divide both sides by 

Cancel out common factors

Take square roots of both sides

Evaluate the right-hand sides

Make r the subject

Hence, the resulting equating for r is:

Read more about the subject of formulas at:
brainly.com/question/21866313
 
        
             
        
        
        
Answer:
1. 2^9 = 512
2. 2^3 = 8
3. 7^3 = 343
4. 6^3 = 216
5. 3^6 = 729
Step-by-step explanation:
To start we have to express the number as a multiplication of prime numbers, from there we can take the expression as a power
1. 
2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 = 512
2^9 = 512
2. 
2 x 2 x 2 = 8
2^3 = 8
3. 
7 x 7 x 7 = 343
7^3 = 343
4. 
6 x 6 x 6 = 216
6^3 = 216
5. 
3 x 3 x 3 x 3 x 3 x 3 = 729
3^6 = 729
 
        
             
        
        
        
Using it's concept, it is found that the relative frequency  probability of rolling an even number based on this experiment is  .
.
A relative frequency is the <u>number of desired outcomes divided by the number of total outcomes</u>.
In this problem:
- 50 dices are thrown, hence  . .
- 22 resulted in an even number, hence  
The <u>relative frequency</u> is given by:

A similar problem is given at brainly.com/question/20630951
 
        
             
        
        
        
I believe it is commutative property cause the numbers didn't change instead they just switched places in the equation.