RD Sharma Solutions Class 10 Maths Chapter 8 Exercise 8.3: Chapter 8, Exercise 8.3 of RD Sharma's Class 10 Maths focuses on solving quadratic equations using the quadratic formula. This exercise emphasizes the formula , which is derived from the standard quadratic equation.
Students learn to calculate the discriminant (D), and its role in determining the nature of roots—real and distinct ( D>0 ), real and equal ( D=0 ), or imaginary ( D<0 ). The problems enhance conceptual understanding and application skills for solving quadratic equations systematically.RD Sharma Solutions Class 10 Maths Chapter 8 Exercise 8.3 PDF
Solve the following quadratic equation by factorization:
1. (x – 4)(x + 2) = 0
Solution:
Given, (x – 4) (x + 2) = 0 So, either x – 4 = 0 ⇒ x = 4 Or, x + 2 = 0, ⇒ x = – 2 Thus, the roots of the given quadratic equation are 4 and -2, respectively.2. (2x + 3) (3x – 7) = 0
Solution:
Given, (2x + 3) (3x – 7) = 0. So, either 2x + 3 = 0, ⇒ x = – 3/2 Or, 3x -7 = 0, ⇒ x = 7/3 Thus, the roots of the given quadratic equation are x = -3/2 and x = 7/3, respectively.3. 3x 2 – 14x – 5 = 0
Solution:
Given. 3x 2 – 14x – 5 = 0 ⇒ 3x 2 – 14x – 5 = 0 ⇒ 3x 2 – 15x + x – 5 = 0 ⇒ 3x(x – 5) + 1(x – 5) = 0 ⇒ (3x + 1)(x – 5) = 0 Now, either 3x + 1 = 0 ⇒ x = -1/3 Or, x – 5 = 0 ⇒ x = 5 Thus, the roots of the given quadratic equation are 5 and x = – 1/3, respectively.4. Find the roots of the equation 9x 2 – 3x – 2 = 0.
Solution:
Given, 9x 2 – 3x – 2 = 0. ⇒ 9x 2 – 3x – 2 = 0. ⇒ 9x 2 – 6x + 3x – 2 = 0 ⇒ 3x (3x – 2) + 1(3x – 2) = 0 ⇒ (3x – 2)(3x + 1) = 0 Now, either 3x – 2 = 0 ⇒ x = 2/3 Or, 3x + 1= 0 ⇒ x = -1/3 Thus, the roots of the given quadratic equation are x = 2/3 and x = -1/3, respectively.
5.
Solution:
Given,
6. 6x 2 + 11x + 3 = 0
Solution:
Given equation is 6x 2 + 11x + 3 = 0. ⇒ 6x 2 + 9x + 2x + 3 = 0 ⇒ 3x (2x + 3) + 1(2x + 3) = 0 ⇒ (2x +3) (3x + 1) = 0 Now, either 2x + 3 = 0 ⇒ x = -3/2 Or, 3x + 1= 0 ⇒ x = -1/3 Thus, the roots of the given quadratic equation are x = -3/2 and x = -1/3, respectively.7. 5x 2 – 3x – 2 = 0
Solution:
Given equation is 5x 2 – 3x – 2 = 0. ⇒ 5x 2 – 3x – 2 = 0. ⇒ 5x 2 – 5x + 2x – 2 = 0 ⇒ 5x(x – 1) + 2(x – 1) = 0 ⇒ (5x + 2)(x – 1) = 0 Now, either 5x + 2 = 0 ⇒x = -2/5 Or, x -1= 0 ⇒x = 1 Thus, the roots of the given quadratic equation are 1 and x = -2/5, respectively.8. 48x 2 – 13x – 1 = 0
Solution:
Given equation is 48x 2 – 13x – 1 = 0. ⇒ 48x 2 – 13x – 1 = 0. ⇒ 48x 2 – 16x + 3x – 1 = 0. ⇒ 16x(3x – 1) + 1(3x – 1) = 0 ⇒ (16x + 1)(3x – 1) = 0 Either 16x + 1 = 0 ⇒ x = -1/16 Or, 3x – 1=0 ⇒ x = 1/3 Thus, the roots of the given quadratic equation are x = -1/16 and x = 1/3, respectively.9. 3x 2 = -11x – 10
Solution:
Given equation is 3x 2 = -11x – 10 ⇒ 3x 2 + 11x + 10 = 0 ⇒ 3x 2 + 6x + 5x + 10 = 0 ⇒ 3x(x + 2) + 5(x + 2) = 0 ⇒ (3x + 5)(x + 2) = 0 Now, either 3x + 5 = 0 ⇒ x = -5/3 Or, x + 2 = 0 ⇒ x = -2 Thus, the roots of the given quadratic equation are x = -5/3 and -2, respectively.10. 25x(x + 1) = – 4
Solution:
Given equation is 25x(x + 1) = -4 25x(x + 1) = -4 ⇒ 25x 2 + 25x + 4 = 0 ⇒ 25x 2 + 20x + 5x + 4 = 0 ⇒ 5x (5x + 4) + 1(5x + 4) = 0 ⇒ (5x + 4)(5x + 1) = 0 Now, either 5x + 4 = 0 therefore x = – 4/5 Or, 5x + 1 = 0 therefore x = -1 /5 Thus, the roots of the given quadratic equation are x = – 4/5 and x = -1/5, respectively.11. 16x – 10/x = 27
Solution:
Given, 16x – 10/x = 27 On multiplying x on both sides we have, ⇒ 16x 2 – 10 = 27x ⇒ 16x 2 – 27x – 10 = 0 ⇒ 16x 2 – 32x + 5x – 10 = 0 ⇒ 16x(x – 2) +5(x – 2) = 0 ⇒ (16x + 5) (x – 2) = 0 Now, either 16x + 5 = 0 ⇒ x = -5/16 Or, x – 2 = 0 ⇒ x = 2 Thus, the roots of the given quadratic equation are x = – 5/16 and x = 2, respectively.
12.
Solution:
Given equation is,
13. x – 1/x = 3, x ≠ 0
Solution:
Given, x – 1/x = 3 On multiplying x on both sides, we have, ⇒ x 2 – 1 = 3x ⇒ x 2 – 3x – 1 = 014.
Solution:
Given,
15.
Solution:
Given,16. a 2 x 2 – 3abx + 2b 2 = 0
Solution:
Given equation is a 2 x 2 – 3abx + 2b 2 = 0 ⇒ a 2 x 2 – abx – 2abx + 2b 2 = 0 ⇒ ax(ax – b) – 2b(ax – b) = 0 ⇒ (ax – b)(ax – 2b) = 0 Now, either ax – b = 0 ⇒ x = b/a Or, ax – 2b = 0 ⇒ x = 2b/a Thus, the roots of the quadratic equation are x = 2b/a and x = b/a, respectively.17. 9x 2 – 6b 2 x – (a 4 – b 4 ) = 0
Solution:
Given,18. 4x 2 + 4bx – (a 2 – b 2 ) = 0
Solution:
Given, 4x 2 + 4bx – (a 2 – b 2 ) = 0 For factorizing, 4(a 2 – b 2 ) = -4(a – b) (a + b) = [-2(a-b)] [2(a + b)] ⇒ 2(b – a)*2(b + a) ⇒ 4x 2 + (2(b – a) + 2(b + a)) – (a – b)(a + b) = 0 So, now 4x 2 + 2(b – a)x++ 2(b + a)x + (b – a)(a + b) = 0 ⇒ 2x(2x + (b – a)) +(a + b)(2x + (b – a)) = 0 ⇒ (2x + (b – a))(2x + b + a) = 0 Now, either (2x + (b – a)) = 0 ⇒x = (a – b)/2 Or, (2x + b + a) = 0 ⇒ x = -(a + b)/2 Thus, the roots of the given quadratic equation are x = -(a + b)/2 and x = (a – b)/2, respectively.19. ax 2 + (4a 2 – 3b)x – 12ab = 0
Solution:
Given equation is ax 2 + (4a 2 – 3b)x – 12ab = 0 ⇒ ax 2 + 4a 2 x – 3bx – 12ab = 0 ⇒ ax(x + 4a) – 3b(x + 4a) = 0 ⇒ (x + 4a)(ax – 3b) = 0 Now, either x + 4a = 0 ⇒ x = -4a Or, ax – 3b = 0 ⇒ x = 3b/a Thus, the roots of the given quadratic equation are x = 3b/a and -4a, respectively.20. 2x 2 + ax – a 2 = 0
Solution:
Given,
21. 16/x – 1 = 15/(x + 1), x ≠ 0, -1
Solution:
Given,
22. x ≠ -2, 3/2
Solution:
Given,
23. x ≠ 3, 4
Solution:
The given equation is24. x ≠ 0, 2
Solution:
Given equation is,
25.
Solution:
Given equation is,
26.
, x ≠ 0Solution:
Given equation is,
27.
, x ≠ 1, -1
Solution:
The given equation is,28.
, x ≠ 1, -1/2
Solution:
The given equation is,
29.
Solution:
Given equation is,30.
Solution:
Given equation is,Conceptual Clarity
Exercise 8.3 focuses on methods to solve quadratic equations, including factorization, completing the square, and using the quadratic formula. Practicing these helps in mastering the fundamental concepts and ensures clarity on the topic.Strengthening Problem-Solving Skills
This exercise offers a variety of problems, enabling students to apply different approaches to solving quadratic equations. Regular practice builds critical thinking and problem-solving abilities.Preparation for Board Exams
Quadratic equations form an important part of the Class 10 Maths syllabus. Solving RD Sharma's problems ensures thorough preparation for board exams as the book aligns well with the NCERT syllabus and exam pattern.Confidence Boost
RD Sharma solutions provide step-by-step explanations for each problem. Following these solutions helps students gain confidence in solving complex problems independently.Enhances Speed and Accuracy
Solving numerous problems improves calculation speed and enhances accuracy, which is crucial for board exams and other competitive exams.Application in Real-Life Problems
Quadratic equations have practical applications in physics, engineering, and other sciences. Understanding how to solve them equips students to handle real-life problems requiring mathematical solutions.Foundation for Higher Studies
Quadratic equations are essential for advanced mathematics, especially in Algebra and Calculus. Solving RD Sharma exercises strengthens the foundation required for higher classes and competitive exams.