x y The Cartesian Plane This presentation is a review of the Cartesian or Co- ordinate Plane. After viewing a slide, click the mouse to move on.

x y Here are three important parts of the plane. y-axis vertical axis x-axis horizontal axis origin (0,0) The grid drawn below is called the Cartesian Plane! Click your mouse to continue. Note the placement of the arrows on the axis.

x y The plane is divided into four quadrants. Each quadrant is commonly represented by a Roman numeral. III III IV second quadrant third quadrantfourth quadrant In the first quadrant, both the x and y values are positive. In the second quadrant, the x value is negative and y value is positive. In the third quadrant, both the x and y values are negative. In the fourth quadrant, both the x value is positive and y value is negative. Click your mouse to continue. In the first quadrant, both the x and y values are positive. I first quadrant In the second quadrant, the x value is negative and y value is positive. II In the third quadrant, both the x and y values are negative. III In the fourth quadrant, both the x value is positive and y value is negative. IV

x y The location of a point can be described on the plane. How could you describe the location of the point shown here? Click your mouse to continue.

x y Start at the origin and think about how many squares you need to go to the right and up to reach the point. (5, 6) 5 6 Click your mouse to continue.

x y (5, 6) is an example of an ordered pair. Ordered pairs are used to describe the location of points on the plane. An ordered pair has two coordinates… x-coordinate y-coordinate (5, 6) 5 6 Click your mouse to continue.

x y x-coordinate y-coordinate (5, 6) The Order Never Changes! The ordered pair is always x before y. (x, y) Or, (horizontal axis, vertical axis) Or, (independent variable, dependent variable)

x y (x, y) in the door up the elevator You might find it helpful to think of it like entering a hotel … (– 3, 4) left 3 up 4 Click your mouse to continue.

x y Try this… plot the following points. Click your mouse on the grid where the point should be plotted. A(– 4, 6) B(2, – 3.5) C(– 6, – 4) D(6¾, 3⅔) These points all lie in different quadrants. What do you notice about their coordinates? Click your mouse to continue.

x y A(– 4, 6) B(2, – 3.5) C(– 6, – 4) D(6¾, 3⅔) What do you notice about their coordinates? In the first quadrant, both the x and y values are positive. In the second quadrant, the x value is negative and y value is positive. In the third quadrant, both the x and y values are negative. In the fourth quadrant, both the x value is positive and y value is negative. Click your mouse to continue.

x y A few more to try…plot the following points. Click your mouse on the grid where the point should be plotted. F(0, 6) E(5, 0) H(0, – 3) G(– 7, 0) H(0, – 3) E(5, 0) These points all lie on the axes, not in quadrants. Click your mouse to continue.