NCERT Solutions for Class 9 Maths Chapter 3 Coordinate Geometry Ex 3.1
NCERT Solutions for Class 9 Maths Chapter 3 Coordinate Geometry Ex 3.1
Ex 3.1 Class 9 Maths Question 1.
How will you describe the position of a table lamp on your study table to another person?
Solution:
To describe the position of a table lamp placed on the table, let us consider the table lamp as P and the table as a plane.
Now choose two perpendicular edges of the table as the axes OX and OY.
Measure the perpendicular distance ‘a’cm of P (lamp) from OY. Measure the perpendicular distance ‘b’ cm of P (lamp) from OX.
Thus, the position of the table lamp P is described by the ordered pair (a, b).
Ex 3.1 Class 9 Maths Question 2.
(Street Plan): A city has two main roads which cross each other at the centre of the city. These two roads are along the North-South direction and East-West direction. All other streets of the city run parallel to these roads and are 200 m apart. There are 5 streets in each direction. Using 1 cm = 200 m, draw a model of the city on your notebook. Represent the roads/streets by single lines.
There are many cross-streets in your model. A particular cross-street is made by two streets, one running in the North-South direction and another in the East-West direction. Each cross street is referred to in the following manner: If the 2nd street running in the North-South direction and 5th in the East-West direction meet at some crossing, then we will call this cross-street (2,5). Using this convention, find:
(i) how many cross-streets can be referred to as (4,3).
(ii) how many cross-streets can be referred to as (3,4).
Solution:
(i) A unique cross street as shown by the point A(4, 3).
(ii) A unique cross street as shown by the point B(3,4).
The two cross streets are uniquely found because of the two reference lines we have used for locating them.
NCERT Solutions for Class 9 Maths Chapter 3 Coordinate Geometry Ex 3.2
NCERT Solutions for Class 9 Maths Chapter 3 Coordinate Geometry Ex 3.3
Coordinate Geometry Class 9 Extra Questions Maths Chapter 3
Extra Questions for Class 9 Maths Chapter 3 Coordinate Geometry