Question:
Which of the following expressions represents the distance between 1.7 and −1/2 on a number line?
Choose 1 answer: 


C. None of the above
Answer:

Step-by-step explanation:
Given
Numbers: 1.7 and -1/2
Required
Determine the distance
To calculate the distance, we start by calculating the difference between the given numbers;

Then, we calculate the distance;
<em>In this case, the distance is meant to be positive; So, we'll introduce the symbol for absolute value;</em>
Hence, 

Substitute  for Difference;
 for Difference;

<em>Hence, the correct option is B</em>
 
        
                    
             
        
        
        
Answer:
The elevator stops on the 19th floor.
Step-by-step explanation:
On the 16th floor, goes up 12 floors:
16 + 12 = 28
On the 28th floor, goes down 7 floors:
28 - 7 = 21
On the 21st floor, does up 3 floors:
21 + 3 = 24
On the 24th floor, goes down 5 floors:
24 - 5 = 19
 
        
             
        
        
        
Answer:
(x, y) = (3, 5/2)
Step-by-step explanation:

I'll solve by elimination here. If you invert the second equation and add it to the first, 2y and -2y would cancel out.

Now just add those from top to bottom.

Nothing else needs to be done for that part. Now, you can pick either equation and use the known value of x to solve for y.

(x, y) = (3, 5/2)