If LN =54 and LM= 31 find MN

Question

Segment Addition Postulate 

Answer 1

These questions are easier if you make a diagram.

First we have LN = 54

L------54-----N

Then we have LM = 31

L----31---M

Which together gives us this:

L-----31---M-------N

|----------54----------|

So LN = LM + MN

MN = LN - LM

MN = 54 - 31

MN = 23