If you take a globe or a map and draw a line through all the points that have
exactly the same longitude, the line you get is the meridian of that longitude.
The line of longitude for a place that is halfway between the prime meridian and the 80th line of longitude and west of the prime meridian would be -40 degrees longitude. The prime meridian is at 0 degrees, and halfway between 0 and 80 is 40 degrees. Since the location is west of the prime meridian, the longitude would be measured as negative.
If you take a globe or a map and draw a line through all the points that haveexactly the same longitude, the line you get is the meridian of that longitude.
90 degrees west longitude
A meridian of longitude is an imaginary line made up of all the points on earth that have the same longitude, whatever that number is. If you draw any meridian of longitude on a globe, it looks like a solid half-circle between the north and south poles.
90 degrees
Every meridian ('line') of longitude is a semicircle on the earth's surface, running between the north and south poles. Every meridian runs through all possible latitudes, and every point on a meridian has the same longitude.
90 degrees west
-- Longitude is the angle east or west between a point on the Earth's surface and the Prime Meridian. -- Latitude is the angle north or south between a point and the equator. -- A meridian is an imaginary line between the north and south poles and through all the points on Earth that have the same one single longitude.
Every point on a meridian has the same longitude.
latitude
The Prime Meridian is a line of longitude, and it sits at 0 degrees longitude.
The time meridian is each standard time zone roughly centered on a line of longitude exactly divisible by 15 degrees and the prime meridian is the starting point for the standard time zones an arbitrary longitude line.