A scatterplot graph is divided into four quadrants due to the (0, 0) intersection point of the horizontal axis (xaxis) and vertical axis (yaxis). This intersection point is called the origin. Both axes extend from negative infinity to positive infinity, resulting in four possible combinations of (x, y) points in the four respective quadrants. You should use Roman numerals to label your quadrants.
First Quadrant

The upperright quadrant, also referred to as the Quadrant I, will only contain points that lie within the range of 0 to positive infinity for both the x and y axis. Therefore, any point, indicated as (x, y), in the first quadrant will be positive at both x and y. So the product of the coordinates [ (+) x, (+) y] will be positive.
Second Quadrant

The upperleft quadrant, or Quadrant II, identifies only points to the left of zero (negative) on the xaxis and points above zero (positive) on the yaxis. Thus, any point in the second quadrant will be negative at the x value and positive at the y value. The product of these coordinates, [ () x, (+) y ], is negative.
Third Quadrant

The lowerleft part of the grid, Quadrant III, identifies points less than zero on both the x and y axes. Any point within this quadrant will be negative at both x and y values. The product of these coordinates, [ () x, () y ], is always positive.
Fourth Quadrant

Quadrant IV, in the lower right of the graph, contains only points that are to the right of zero on the xaxis and below zero on the yaxis; therefore, all points in this quadrant will have a positive x value and a negative y value. The product of these coordinates, [ (+) x, () y ], will be negative.
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