Answer:
21..........
Step-by-step explanation:
 
        
             
        
        
        
Answer is A.
√6 + √2
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    4
        
                    
             
        
        
        
The distance formula is:

We are given two points in the form (x,y), so plug in the values to the distance formula:

Next we can simplify. We know that 12-12 is 0, so we can drop it from the equation, as it will not affect our answer. Also, we know that -10-15 is -25:

The square and square root cancel each other out leaving us with 25.
The answer is 25.
 
        
        
        
It will be the model that has the arrow going to the right with the starting point at 60 having a solid circle.
 
        
             
        
        
        
Answer:
Ray: A
Vertex:AC
Angle:ABX
Parallel lines:CFB FCB BCF
Parallel planes:BCC
Coplanar points:A F
Colliner points:C D E F 
Segment addition postulate:ANB
Prependicular:????