Answer: (3x + 4y)(3x + 4y)
Step-by-step explanation: So you are supposed to "unfoil". So you would find two numbers multiplied together to make 9x^2 which would be 3x. Then you would find two numbers that can be multiplied together to get 16y^2 which would be 4y. To check your work, you do 3x times 3x. Then 4y times 4y. Then 4y times 3x plus 3x times 4y. You get 9x^2 + 24xy plus 16y^2.
 
        
                    
             
        
        
        
The answer will be 2. the gcf of the equation is 2 because 2 goes into 10 by 5 and into 4 by 2 leaving you with 2(5b^2+2a^3).
        
                    
             
        
        
        
<span>you have to create variables that have the same coefficient</span>
        
             
        
        
        
84. Area of a triangle is (base x height) / 2
 
        
             
        
        
        
Answer:
 
And we can find this probability using the complement rule and the normal standard table or excel:
 
The firgure attached illustrate the problem
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".  
Solution to the problem
Let X the random variable that represent the retirement savings of a population, and for this case we know the distribution for X is given by:
 
  
Where  and
 and  
We are interested on this probability
 
And the best way to solve this problem is using the normal standard distribution and the z score given by:
 
If we apply this formula to our probability we got this:
 
And we can find this probability using the complement rule and the normal standard table or excel:
 
The firgure attached illustrate the problem