Hyphens and Dashes. A hyphen joins two or more words together while a dash separates words into parenthetical statements. The two are sometimes confused because they look so similar, but their usage is different. Hyphens are not separated by spaces, while a dash has a space on either side.
We plug in 14 for x when we set the two equations equal to each other to prove they are equal.
So true LM congruent to MN