Answer:
(a) 4
(b) 4 * (7+3)
Step-by-step explanation:
(a) Let's first start by prime factorizing (finding the prime factors) 28 and 12:
12: 2*2*3
28: 2*2*7
We can see here they both share a common factor of 2*2, which is 4, therefore the GCF is 4. 
(b) Factor a 4 out from the equation:

This gives us:
4 * (7+3)
 
        
             
        
        
        
To find the average you add all three numbers together and then divide by three since you added three. 
$38,750.00 + $42,500.00 + $42,500.00 = $123,750.00
$123,750.00 ÷ 3 = $41,250
So your answer is $41,250
        
             
        
        
        
Answer:
1
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer: x=  −6
/5  is the answer
 
        
                    
             
        
        
        
Answer: 14.73
Step-by-step explanation:
The given triangle is a right angle triangle. 
EF^2 + DF^2 = ED^2
The hypotenuse is |ED| while the two shorter legs are |EF| and |DF|.
We can then apply the Pythagoras Theorem to find the length of EF.
(EF)^2 + (DF)^2 = (ED)^2
(EF)^2 + (12)^2 = (19)^2
(EF)^2 + 144 = 361
(EF)^2 = 361 - 144
(EF)^2 = 217
EF = 14.73