Question

Point O is between points M and N on line segment MN. O is the midpoint of line segment MN if _____.

ON = NM
OM = NM
ON + OM = MN
ON = OM

Answer 1

It would probably be best to draw out a line on a graph, perhaps as a completely horizontal or vertical line. Label the endpoints of the line with M and N, and put a point right in between both points such that it is equidistant from both points. If you draw your line horizontally, the ideal points to place them on a graph would be to place Point M on (0,0) and Point N on (0,2) and Point O on (0,1). Vertical line is the same deal. Now label the length of each point, from N to O and from O to M. You should notice something that will answer the question. That being said, that eliminates OM = NM and ON = NM. So now decide which answer best describes a midpoint best.