How exact this is depends on what part of the globe the two places are on and what kind of map projection is used. But, it will give you a good ball park figure. You also need to know how far apart the lines are on the map you are looking at. Most hurricane maps have lines for every five degrees. One way to check this on a map that shows the U.S. East Coast is if one line goes through the northern part of the Florida Keys and the next line to the north is in the Jacksonville, Fla. area, the lines are five degrees apart - at 25 degrees N. and 30 degrees N in this case.
Many maps have dots at each one degree.
When I look at weather maps I get confused about highs and lows and fronts. The triangles and half circles on lines showing fronts indicate the direction of movement. On a cold-front line, the triangles are on the side toward which the cold air is moving. On a warm-front line, the half circles are on the side toward which the warm air is moving. I have not been able to find one.