Glencoe Math: Course 1, Volume 1
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Glencoe Math: Course 1, Volume 1 View details
6. The Coordinate Plane
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Exercise 29 Page 401

The x-coordinate represents the horizontal shift, starting from the origin, and the y-coordinate represents the vertical shift.

Label: B
Quadrant: III

Practice makes perfect
An ( x, y) ordered pair is plotted in a coordinate plane by finding the x-coordinate on the horizontal axis and the y-coordinate on the vertical axis. Let's take a look at the point we want to graph and label on a coordinate plane. ( -1 12, -1 12)

To graph this point we should first move 1 12 units in the negative horizontal direction starting from the origin. Then we should move 1 12 units in the negative vertical direction. We move in the negative direction in both axes because both coordinates are negative numbers.

From the diagram, we see that the point (-1 12,-1 12) matches with the label B. To determine the quadrant in which a point lies without graphing, observe the signs of the x- and y-coordinates.

Quadrant x-coordinate y-coordinate
Quadrant I Positive Positive
Quadrant II Negative Positive
Quadrant III Negative Negative
Quadrant IV Positive Negative
Since both coordinates are negative, B(-1 12,-1 12) lies in Quadrant III.

Extra

Visualizing Quadrants

To help us visualize each of the different quadrants, let's take a look at the diagram.

Therefore, we are able to determine in which quadrant a point is located only by looking at the signs of coordinates of this point.