What is the rate of change for the interval between A and B?
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The slope of this graph is rise over run which means how much your distance x has between the 2 points and how much y increased between those 2 points. So it starts at (1,-2) and ends at (2,1). So x had a run of 1 and y had a rise of 3 we have 3/1 which is equivalent to 3, so the answer would be B.