The document defines key terms related to the coordinate plane, including the x-axis, y-axis, quadrants, coordinates, and ordered pairs. It explains that the quadrants are numbered counter-clockwise, with quadrant I in the upper right and quadrant IV in the lower right. An ordered pair (x,y) locates a point by moving x units right/left from the origin and y units up/down. For example, the point (-3,-2) is in quadrant III, as it is located 3 units left and 2 units down from the origin.

1. The Coordinate Plane February 16, 2010

2. Vocabulary Coordinate Plane – formed by two number lines in a plane that intersect at right angles. The point of intersection is the zero on each number line Axes – the two number lines X-Axis – the horizontal axis Y-Axis – the vertical axis

3. Vocabulary Quadrants – the four sections the axes divide the coordinate plane into Origin – the point where the axes intersect Coordinates – the numbers in an ordered pair X-Coordinate – the first number in a coordinate pair Y-Coordinate – the second number in a coordinate pair

4. Identifying Quadrants The quadrants in the coordinate plane are named counter-clockwise. It starts in the upper right-hand corner with Quadrant I (1), moves to the upper left-hand corner with Quadrant II (2), then drops down to the lower left-hand corner with Quadrant III (3), and finally, moves to the lower right-hand corner with Quadrant IV (4).

5. Locating Points on a Coordinate Plane An ordered pair gives the location of a point on a coordinate plane. The first number tells how far to move right (positive) or left (negative). The second number tells how far to move up (positive) or down (negative). You ALWAYS go left or right first, THEN up or down.

6. Graphing Points on a Coordinate Plane (-3, -2) Look at the very first number. That is your x-coordinate. The negative tells you to go left 3 places from the origin. Next, look at the second number. That is your y-coordinate. The negative tells you to go down 2 places from where you are on the x-axis. Your point should be graphed in the 3 rd Quadrant.