9th Maths 3.1

NCERT Class 9th solution of Exercise 3.2

NCERT Class 9th solution of Exercise 3.3

NCERT Class 9th solution of Exercise 2.1

NCERT Class 9th Projects

Exercise 3.1

Q1. How will you describe the position of a table lamp on your study table to another person?

Sol.

We will measure the distance of the table from the breadth side of the table let it be `p` and the distance from the length side of the table let be `q`. Then the position of the lamp will be described as `(p, q)`.

Q2. (street Plan): A city has main two 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 `1 cm=200m` drawn 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 `2^(nd)` street running in North-South direction and `5^(th)` 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)`.

Sol. :

 The street plan is shown in the figure given below :

i) Only a unique cross-street is reffered to as `(4, 3)` which is denoted in the above figure by point `P`.

ii) Only a unique cross-street is reffered to as `(3, 4)` which is denoted in the above figure by point `Q`.