-----------------------------------------------------
Answer: Your answer is the third one, a function assigns to each input exactly one output.
If you have a true function, there will only be one output for each input, if you had more than one, it isn't a function.
Since the distance of MN is 31 and we have a distance of ML
of h -15 and LN of 2h – 8, therefore
ML + LN = h -15 + 2h – 8 = 31
h = 18
substituting the value of h to the expression for LN
obtaining
LN = 2h – 8
LN = 2(18) – 8
LN = 28
Therefore the length of the segment LN is 28 units
