# RD Sharma Class 9 Chapter 11 Solutions (Coordinate Geometry)

RD Sharma Class 9 Maths Solutions for Chapter 11** **are prepared with a perspective to help you in gaining clarity in coordinate geometry. The topics covered in this chapter of RD Sharma Solutions are the cartesian plane or the rectangular coordinate system, cartesian axes, and the four quadrants in a cartesian system. You will learn to plot the points on using their cartesian coordinates. This chapter has almost negligible chances of error if you practice it rigorously. This topic will fetch you a lot of marks in both your school exams or other exams of national level such as Olympiads or NTSE.

There are 2 questions covering the topics of your syllabus in 1 exercise. These questions will require you to have detailed knowledge about plotting points on the x-y plane on a graph. You will have to keep revising these questions regularly to memorize the concepts in this chapter. With consistent practice, you can develop a strong foundation for various subjects in your higher classes. The questions in Class 9 RD Sharma Chapter 11 are based on the latest exam patterns and therefore, you will get an idea about the types of questions that come in the exams.

All the solutions in this chapter by the Instasolv faculty are based on the guidelines prescribed by CBSE. You can use our answers as a reliable source of reference because we cover each question of the exercise with complete accuracy and in a precise format. This will help understand how to approach a question of coordinate geometry in the right way to hit the correct answer in your first attempt. Solving these questions with our assistance will help you achieve good grades in your school exams.

## Important Topics for RD Sharma Solutions for Class 9 Chapter 11: Coordinate Geometry

**Introduction to the Cartesian Plane**

When two lines, one horizontal and another vertical intersect each other at the right angle, then the plane and the system of coordinates are termed as the cartesian plane. The point of intersection of these two perpendicular lines (which are called the x-axis and y-axis respectively) is known as the origin and is denoted by O.

**Quadrants**

- The axes of the cartesian plane divide the plane into 4 equal parts which are termed as I, II, III, and IV quadrants respectively starting from the top right corner and moving in the anti-clockwise direction.
- The symbols of the abscissa and the ordinate in the first quadrant are (+,+), in the second quadrant, it is (-.+), in the third quadrant, it is (-,-), and in the fourth quadrant it is (+,-). The plus sign denotes positive real numbers, whereas the minus sign denotes negative real numbers.

**Basic Terms in Coordinate Geometry**

- Abscissa: The x-coordinate of a point, which refers to the distance of a given point from the y-axis is called Abscissa.
- Ordinate: The y-coordinate of a point in consideration, which describes the distance of the given point from the x-axis is called the ordinate.

While denoting the coordinates of a point we use the following format

(abscissa of the point, the ordinate of the point).

**Distance Formula**

Let us consider 2 points and their coordinates as P(x_{1}, y_{1}) and Q(x_{1}, y_{1}) respectively, then the distance between these two given points can be given by the distance formula such that,

The result of the evaluation of a distance is always a positive value.

The distance of the point P(x, y) from the origin O(0, 0) is given such that,

**Section Formula**

If a point P divides a given line segment internally, with end-points as A(x_{1}, y_{1}) and B(x_{2}, y_{2})into a ratiom1:m2, then the coordinates of the point P are given as

Therefore, if we are to find the mid-point of a line segment with end-points P(x_{n}, y_{1}) and Q(x_{n}, y_{2}), the coordinates will be given as

**Area of a Triangle and Collinearity of 3 Points**

Let us consider three vertices of a given triangle with their respective coordinates as P(x_{1}, y_{1}), Q(x_{2}, y_{2}) and R(x_{3}, y_{3}), in this case, the area of the triangle PQR is given as

If we have to check the collinearity of three points, we should check if the coordinates of the given points form a triangle with area equal to 0.

### Exercise Discussion for RD Sharma Solutions for Class 9 Chapter 11: Coordinate Geometry

There is only one exercise in Chapter 11 of RD Sharma Class 9 Maths Solutions. The questions are based on the plotting of given points on the cartesian plane using a graph paper. You will also get to solve a question in which you will need to identify the coordinate points that are already plotted on the graph. Solving these questions will give you ample opportunity to brush your skills in coordinate geometry.

## Benefits of RD Sharma Solutions for Class 9 Chapter 11: Coordinate Geometry by Instasolv

- The maths experts of Instasolv have made sure that you grasp the core concept of the cartesian system and coordinate geometry through simple and step by step solutions.
- Instasolv is a platform that has an objective to provide a hustle-free solution base for you to get your doubts cleared at just one place.
- We provide you with free of cost solutions for all RD Sharma Class 9 Maths chapters.