1. The Cartesian plane is a two-dimensional coordinate system defined by two perpendicular axes: the x-axis (horizontal) and the y-axis (vertical). 2. Each point on the plane is represented by an ordered pair $(x,y)$, where $x$ is the horizontal coordinate and $y$ is the vertical coordinate. 3. The origin is the point $(0,0)$ where the x-axis and y-axis intersect. 4. The plane is divided into four quadrants: - Quadrant I: $x>0$, $y>0$ - Quadrant II: $x<0$, $y>0$ - Quadrant III: $x<0$, $y<0$ - Quadrant IV: $x>0$, $y<0$ 5. To plot a point, start at the origin, move $x$ units along the x-axis, then move $y$ units parallel to the y-axis. 6. The Cartesian plane is fundamental for graphing equations, analyzing geometric shapes, and solving algebraic problems involving two variables. Final answer: The Cartesian plane is a coordinate system with perpendicular x and y axes used to locate points by ordered pairs $(x,y)$.