**Download NCERT Solutions for Class 9 Maths Chapter 3 Exercise 3.1 – Coordinate Geometry**

**1. How will you describe the position of a table lamp on your study table to another person?**

** ****Solution :**

** **Let’s define the front side as the side at which I place my chair to study.(Just like defining an origin on a coordinate plane.)

Now I will describe the position of the table lamp as “It is placed at a distance of **a units **from the right end w.r.t. the front side and **b units** from the opposite end w.r.t. the front side.”

**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 the other streets of the city run parallel to these roads and are 200 m apart. There ****are about 5 streets in each direction. Using 1cm = 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 :**

Both the cross-streets are shown in the figure. It can be seen that there is only one cross-street which can be referred as (4, 3), and again, only one which can be referred as (3, 4).

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