4th yr.- Ruby

And

Ernesto Rondon Highschool

Presents

Cartesian Plane

(A lecture presentation in Math 4 )

Prepared by: Joe Olivare

IVYr.- Ruby

What is Cartesian Plane ?

Cartesian Plane :

- or Cartesian Coordinate System specifies each point uniquely in a plane by a pair of numerical coordinates which are the signed distances from the point to two fixed perpendicular directed lines, measured in the same unit of length.

- It’s main function is to plot or graph ordered pairs (x,y).

Rene Descartes -inventor of cartesian coordinate system.

Different Parts & Functions of Cartesian Plane

X-

axis

Y-axis

Origin

Quadrant I

Quadrant II

Quadrant III

Quadrant IV

(+,+)

(-,+)

(-,-) (+,-)

(0,0)

The 2 Cartesian Coordinates :

- The X-coordinate /X-axis/abcissa is

the horizontal line in the graph.

- The

Y-coordinate/Y-axis/ordinate is the vertical line in the graph.

- The coordinates are written as an ordered pair (x, y) and they are perpendicular to each other.

Other terms for : X

X-coordinate

abcissa

Y

Y-coordinate

ordinate

domainRange

Independent variable

Dependent variable

Origin :

- the origin is the point of intersection of (x,y) with the coordinates (0,0).

Quadrants : -The axes of a two- dimensional Cartesian system divide the plane into four infinite regions, called quadrants, each bounded by two half-axes.

Different Regions :

- Quadrant I is positive to positive(+,+).

- Quadrant II is negative to positive(-,+).

- Quadrant III is negative to negative(-,-).

- Quadrant IV is positive to negative(+,-).

Plotting Points

Here’s an example :Suppose you were told to locate using a map "(3, 5)" (pronounced as "the point three five" or just “three two") on the place. Where would you look? To understand the meaning of "(3, 5)", you have to know the following rule: The x-coordinate (the number for the x-axis) always comes first. The first number (the first coordinate) is always on the horizontal axis.

Ready

Here’s how:

So, for the point (3, 5), you would start at the "origin", the spot where the axes cross:then count over to “three" on

the x-axis:

then count up to “five", moving parallel to the y-axis:and then draw in the dot:

Exerc

ises

Now, you learned to plot and graph, let see how good are you now in this activity…

PROCEED

1. (4, -5) 2. (-3, -1)

Plot the following :

Reveal the answer

:

(4, -5)

(-3,-1)

Answers :

Great job!! Now you’ve survived this activity…

So, What are the things that you learned about Cartesian planes ?..

Hope you enjoyed !!..

Prepared by: Joe olivare