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Name: Jennifer B.
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Why do coordinate graphs go counter-clockwise?

I do not have a good answer. I think it is just convention because somewhere in the haze of history someone decided '+ X' is to the right and '+Y' is up. It is just a convention.

Vince Calder


I do not know for certain. If it is like so many other things in math, it was just a preference of the first people to do graphs. The first number lines would have been like ours, positive to the right. When adding on the vertical (or y) axis, they would have made up be positive. They would also have started things on the axis they had first, the x-axis. Graphs would then go to the new axis, the y-axis. This makes a counter-clockwise coordinate system.

Dr. Ken Mellendorf
Physics Professor
Illinois Central College

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