Exercise 1.1 Class 9 Maths Solutions | Ganita Manjari

Get step-by-step Exercise 1.1 Class 9 Maths Solutions of Ganita Manjari NCERT book with easy explanations for CBSE students.

Welcome to Sid Classes, your trusted destination for comprehensive academic resources! In this detailed study guide, we present complete, step-by-step solutions for NCERT Class 9 Maths Ganita Manjari Chapter 1 Exercise 11 Orienting Yourself: The Use of Coordinates. Designed to reflect how top-scoring students write their solutions and reasoning in school examinations, this walkthrough covers basic coordinate geometry concepts, calculating distances, evaluating door widths, and determining wheelchair accessibility using ordered pairs on a graph.

🔑 Key Concepts & Principles:

  • Coordinate Geometry Basics: Locating positions on a plane using perpendicular axes—the horizontal x-axis and vertical y-axis.
  • Origin & Ordered Pairs: The intersection point of both axes is called the origin \((0,0)\). Points are defined by ordered pairs \((x, y)\).

NCERT Class 9 Maths Ganita Manjari Chapter 1 Exercise 1.1 Solutions

Question 1

Fig. 1.3 shows Reiaan’s room with points \(OABC\) marking its corners. The x- and y-axes are marked in the figure. Point \(O\) is the origin.

Referring to Fig. 1.3, answer the following questions:

(i) If \(D_1 R_1\) represents the door to Reiaan’s room, how far is the door from the left wall (the y-axis) of the room? How far is the door from the x-axis?

Solution:

* Point \(D_1\) is located at \((8, 0)\) and point \(R_1\) at \((11.5, 0)\). The x-coordinate of \(D_1\) is 8, which means the door is 8 units away from the left wall (the y-axis).
* Since both \(D_1\) and \(R_1\) lie directly on the x-axis (y-coordinate = 0), the door is 0 units away from the x-axis.

(ii) What are the coordinates of \(D_1\)?

Solution:

The coordinates of \(D_1\) are \((8, 0)\).

(iii) If \(R_1\) is the point \((11.5, 0)\), how wide is the door? Do you think this is a comfortable width for the room door? If a person in a wheelchair wants to enter the room, will he/she be able to do so easily?

Solution:

* Width of the door: \(\text{Distance} = 11.5 - 8 = \mathbf{3.5\text{ units}}\).
* Yes, 3.5 units provides a very comfortable width for a room door.
* A person using a wheelchair can easily enter the room through this door without difficulty.

(iv) If \(B_1 (0, 1.5)\) and \(B_2 (0, 4)\) represent the ends of the bathroom door, is the bathroom door narrower or wider than the room door?

Solution:

* Width of the bathroom door: \(\text{Distance} = 4 - 1.5 = \mathbf{2.5\text{ units}}\).
* Comparing the two widths: Since \(2.5\text{ units} < 3.5\text{ units}\), the bathroom door is narrower than the main room door.


Frequently Asked Questions (FAQs)

Q1. What is Exercise 1.1 Class 9 Maths about?
A: Exercise 1.1 introduces the basics of coordinate geometry, including axes, origin, coordinates, and locating points on a graph.

Q2. Are these Exercise 1.1 solutions based on the latest CBSE syllabus?
A: Yes, these step-by-step solutions are prepared according to the latest CBSE and NCERT Ganita Manjari syllabus.

Q3. Why is coordinate geometry important in Class 9 Maths?
A: Coordinate geometry helps students understand algebraic plotting, spatial awareness, and navigation, forming a core foundation for higher mathematics.

Q4. What is the origin in coordinate geometry?
A: The point where the x-axis and y-axis intersect is called the origin, represented by the ordered pair \((0, 0)\).

Q5. Where is coordinate geometry used in real life?
A: It is widely used in GPS navigation systems, architectural layouts, digital mapping, engineering designs, and computer graphics.


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Last updated according to the latest NCERT and CBSE syllabus.