Understanding the basic shapes and their properties is an important part of learning mathematics. One of the key topics in geometry is Lines and Angles, which helps you see how different shapes are formed and how they interact. In Chapter 14 of Class 7 RD Sharma Maths, you will learn all about straight lines, angles, and how they are related to each other.
This chapter introduces you to different types of lines, such as parallel lines, intersecting lines, and transversal lines. You will also learn about various types of angles, like acute, right, obtuse, straight, and reflex angles. The chapter also explains angle pairs like complementary, supplementary, adjacent, and vertically opposite angles in a simple and clear way. These concepts are not only important for your exams but are also useful in real life. For example, when you look at the hands of a clock or the corners of a book, you are actually looking at angles. Learning how to measure and understand angles can help improve your problem-solving skills in geometry and beyond.
Do Check: RD Sharma Solutions for Class 7 Maths
The RD Sharma Solutions for Chapter 14 are designed to help you understand each topic easily. These solutions cover all the questions in the textbook, step by step, with simple explanations. Whether it’s solving for unknown angles or understanding angle properties, these solutions will help you master the chapter confidently. By using RD Sharma solutions, you will be able to practice more effectively, clear your doubts, and score better in your exams.
Download RD Sharma Solutions for Class 7 Maths Chapter 13 Simple Interest PDF Here
You can download the RD Sharma Solutions for Class 7 Maths Chapter 13 – Simple Interest PDF from here to study anytime and anywhere. This PDF includes easy-to-understand answers to all the questions given in the textbook. The solutions are written in simple steps so that students can learn the formulas and methods without any confusion. Whether you want to revise before exams or practice more questions, this PDF will help you a lot.
Access Answers to RD Sharma Solutions for Class 7 Maths Chapter 14 Lines and Angles
Q1. What is the supplementary angle for each of the following?
(i) 70°: To get the supplement, subtract 70° from 180°.
180° - 70° = 110°.
(ii) 120°: Subtract 120° from 180°.
180° - 120° = 60°.
(iii) 135°: Subtracting 135° from 180° gives
180° - 135° = 45°.
(iv) 90°: 180° - 90° = 90°. So, the supplement is also 90°.
Q2. Which of these pairs of angles are complementary or supplementary?
(i) 25° and 65°: 25° + 65° = 90°. Since their total is 90°, they are complementary.
(ii) 120° and 60°: 120° + 60° = 180°, which means they are supplementary.
(iii) 63° and 27°: 63° + 27° = 90°, so they form a complementary pair.
(iv) 100° and 80°: 100° + 80° = 180°, hence this is a supplementary pair.
Q3. Can two angles of these types be supplementary?
(i) Both Obtuse: No. An obtuse angle is more than 90°, so two of them together will always be more than 180°, which cannot be supplementary.
(ii) Both Right: Yes. A right angle is 90°, and 90° + 90° = 180°, so two right angles are supplementary.
(iii) Both Acute: No. An acute angle is less than 90°, and two such angles will always total less than 180°.
Q4. If two supplementary angles are equal, what is the measure of each angle?
Let the two equal angles be x. Since their total must be 180°, we write:
x + x = 180°
2x = 180°
x = 180° ÷ 2 = 90°
So, each angle is 90°.
Q5. If the complement of an angle is 28°, what is the supplement of that angle?
Let the angle be x.
x + 28° = 90° (since it is the complement)
x = 90° - 28° = 62°
Now, the supplement of 62° is:
180° - 62° = 118°
Q6. One of the angles in a linear pair is a right angle. What is the other angle?
If one angle is 90° and the total of a linear pair is 180°, then:
Other angle = 180° - 90° = 90°
So, the other angle is also a right angle.
Q7. One angle of a linear pair is obtuse. What is the type of the second angle?
An obtuse angle is more than 90°. Since the total of a linear pair is 180°, the second angle must be less than 90°, which is an acute angle.
Q8. One angle of a linear pair is acute. What is the nature of the other angle?
An acute angle is less than 90°. To make the total 180°, the second angle must be more than 90°, so it is an obtuse angle.
Q9. Is it possible for two acute angles to form a linear pair?
No. Two acute angles add up to less than 180°, so they cannot form a linear pair.
Q10. The supplement of an angle is 65°. Can it have a complement? If yes, what is it?
Let the angle be x.
x + 65° = 180° → x = 115°
A complement must total 90°. But 115° is more than 90°, so it does not have a complement.