slope is rise over run. Take two points (2,0) and (3,1) to get from (2,0) to (3,1) you go down one (-1) and right 3 (+3) rise over run would be -1/3!!!!!!!! y=-1/3x+2
the second pic-------- positive is when the line is pointing right negative is when the line is pointing left no slope is when it is a straight up or down line undefined is when its not straight (curvy)
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