Answer: 15 units
Step-by-step explanation:
Given
The endpoints of the line segment are 
The length of the line segment is given by the distance formula i.e.

Insert the values,

Therefore, the length of line segment TU is 15 units
No, it is not a function....for it to be a function, it cant have any repeating x values...they all have to be different....they can have repeating y values, just not the x ones.....also, it does not pass the vertical line test
The integer would be
positive 5
Don't know try something else it will probably help