1. Rectangular Coordinate System

2. Definitions X-axis – the horizontal axis Y –axis – the vertical axis
Rectangular coordinate system: where the x-axis and the y-axis intersect
Ordered pair: identifies the location of a point on the rectangular coordinate system
(x coordinate, y coordinate)
Origin: (0,0) – intersection of the x and y axis
Quadrant: a section of the rectangular coordinate system

4. How to identify a point? First locate the origin
Second, determine if you are going left or right from the origin
If you go left, your x –coordinate is negative
If you go right, your x –coordinate is positive

5. Third, determine if you are going up or down from the origin
If you go down, your y –coordinate is negative
If you go up, your y –coordinate is positive

6. How to graph a point? First Locate the origin
Second, graph your x -coordinate:
IF the value of your x coordinate is positive move to the right, if negative move to the left
Third, graph your y -coordinate:
IF the value of your y- coordinate is positive move up, if negative move down

7. How to identify the quadrant?
First – locate where your point is
Second – check your graph on which quadrant it is in.

8. Determine if an ordered pair is a solution
Substitute your ordered pair into the equation:
Check to see if the statement is true.
Example:
3x – y = 12
Is (0, 12) a solution?
3(0) – (12) = 12
0 – 12 = 12
No, therefore (0,12) is not a solution
Example: 3x – y = 12
Is (1, -9) a solution?
Example: y = -2x
Is (-3, 8) a solution?
Example: x = 9
Is (4, 9) a solution?

9. Find the missing coordinate
First substitute the given coordinate into the equation.
Example:
X + 2y = 8
( ____, 9)
X + 2(9) = 8
Simplify and solve for the missing coordinate
X + 18 = 8
X = -10

10. Practice X – 4y = 4 (____, -2) 3x + y = 9 ( 4, ____) -2x + 7y = 14
(3, _____)
(_____, 5)
Y = 9
(5, ___)
(____, 9)