Question 65754
How would you describe a rectangular coordinate system? Explain what information is needed to locate a point in a coordinate system.
IN A 2 DIMENSIONAL PLANE,WE NEED REFERENCE WITH RESPECT TO 2 DIRECTIONS
 TO FIX A POINT.
FOR EXAMPLE IN OUR ROAD NET WORK,WE HAVE A HOUSE LOCATED ON SAY 
24 TH. MAIN AND 36TH.CROSS.
THE MAIN ROADS AND CROSSROADS ARE INCLINED TO EACH OTHER COULD BE
 90 DEGREES OR DIFFERENT.
IF WE HAVE TO FIX THE DISTANCES WE TAKE A REFERENCE POINT SAY A CITY
CENTER, TRAVEL 1 MILE ON 24TH MAIN AND 2 MILES ON 36TH. CROSS TO REACH HOME.
AS LONG AS WE HAVE ALL THE HOUSES AT ROAD LEVEL,THIS WOULD DO TO FIX 
THE LOCATION.ONLY WHEN WE HAVE MULTI STOREYED APARTMENTS,WE NEED 
ANOTHER REFERENCE...HEIGHT .
HERE RESTRICTING OUR ATTENTION TO 2 DIMENSION PLANES     
LET US CALL THE MAIN AND CROSS ROADS AS X AND Y AXIS. THE CITY CENTER ,
OUR REFERENCE POINT AS THE ORIGIN 'O'.WE TAKE IT AS AT THE INTERSECTION 
OF THE 2 AXES.IF THE 2 AXES(MAIN AND CROSS ROADS) ARE 
PERPENDICULAR,WE CALL THAT A RECTANGULAR COORDINATE SYSTEM.
WE CALL THE X AXIS AS X'OX....X' ON LEFT FOLLWED BY O ON THE RIGHT 
AND X ON FURTHER RIGHT.ALONG THIS AXIS ALL DISTANCES ARE MEASURED FROM O 
AND TOWARDS X ARE +VE,WHILE DISTANCES TOWARDS X' AS -VE.
SIMILARLY,WE CALL THE Y AXIS AS Y'OY...Y' AT THE BOTTOM FOLLOWED BY O AT
THE TOP AND Y FURTHER UP.AGAIN ALL DISTANCES ALONG THIS AXIS ARE MEASURED 
FROM O AND TOWARDS Y ARE +VE,WHILE DISTANCES TOWARDS Y' AS -VE.