Linear Equations in Two Variables Class 9 important questions with answers PDF download
FAQs on CBSE Important Questions for Class 9 Maths Linear Equations in Two Variables - 2025-26
1. What are the most frequently asked 1-mark important questions from CBSE Class 9 Maths Chapter 4, Linear Equations in Two Variables?
For the 2025-26 exams, common 1-mark questions focus on foundational concepts. You can expect questions that require you to:
- Check if a given ordered pair (x, y) is a solution to a given linear equation.
- Express a given equation in the standard form ax + by + c = 0 and identify the values of a, b, and c.
- Write the equation of a line that is parallel to the x-axis or y-axis, such as y = k or x = k.
2. Which types of questions on graphing linear equations in two variables are considered important for 3-mark or 4-mark sections?
For higher marks, questions often require multiple steps and a clear understanding of graphical representation. Important types include:
- Drawing the graph of a given linear equation on the Cartesian plane.
- Finding the coordinates of the points where the graph intersects the x-axis and y-axis.
- Using the graph to find the area of the triangle formed by the line and the coordinate axes.
- Solving a word problem by first framing the linear equation and then representing it graphically.
3. What kind of word problems from Chapter 4 are important for the Class 9 Maths exam?
Application-based word problems are considered High Order Thinking Skills (HOTS) questions and are very important. Key scenarios to practice include:
- Problems related to taxi fares, where there is a fixed charge for the first kilometre and subsequent charges for the distance covered.
- Situations involving cost, where the price of two different items (like pens and notebooks) is related.
- Problems converting temperature scales (Celsius to Fahrenheit).
4. How are questions related to equations of lines parallel to the x-axis and y-axis typically tested?
These questions test your understanding of special cases of linear equations. An important question might ask you to represent an equation like y = 3 geometrically in both one variable (on a number line) and two variables (on a Cartesian plane). In one variable, it's a point. In two variables, it's a line parallel to the x-axis. This distinction is a key concept for exams.
5. What is a common conceptual trap or misconception in questions about the solutions of a linear equation?
A very common trap is for students to forget that a single linear equation in two variables has infinitely many solutions. An important question might ask you to find two or three different solutions for an equation like 2x + y = 7. Any point (x, y) that lies on the line representing this equation is a valid solution, not just a single, unique pair.
6. From an exam perspective, why is it crucial to master framing an equation from a word problem?
Mastering the framing of equations is crucial because it is the first and most critical step in solving any application-based problem, which often carry higher marks (3 to 5 marks). Examiners use these questions to test your ability to apply mathematical concepts to real-world contexts, moving beyond simple calculation. If the initial equation is incorrect, all subsequent steps, including graphing and finding solutions, will also be wrong, leading to a significant loss of marks.
7. How does knowing that the graph of a linear equation is always a straight line help in answering important exam questions?
This fundamental property is key to solving and verifying problems. For instance, an important question might ask if three given points are collinear. You can form a linear equation using two of the points and then check if the third point satisfies the equation. If it does, all three points lie on the same straight line and are therefore collinear. This method is faster and more accurate than just plotting and visually inspecting.
8. What is the importance of finding the points where a line intersects the coordinate axes?
Finding the axis-intercepts is an important skill for multiple reasons. Firstly, these two points are the easiest to find to plot the graph of the line. To find the x-intercept, you set y = 0, and for the y-intercept, you set x = 0. Secondly, these points are often used in questions that ask you to calculate the area of the triangle formed by the line and the axes, which is a common 3-mark question.











