0 AnilSinghBoraGuru Asked: July 14, 20212021-07-14T17:09:28+05:30 2021-07-14T17:09:28+05:30In: NCERT Class 10th Maths In a ∆ABC, ∠ C = 3 ∠ B = 2 (∠A + ∠ B). Find the three angles. Q.5 0 How i find the Angles of the given question. Because it is very important for board exams as well as competitive exams. In a ∆ABC, ∠ C = 3 ∠ B = 2 (∠A + ∠ B). Find the three angles. best solutionexercise 3.7 ncertncert class 10th solutionpair of linear equations in two variables ncert Share Facebook 1 Answer Voted Oldest Recent bhagwansingh Guru 2021-07-14T17:39:15+05:30Added an answer on July 14, 2021 at 5:39 pm Given, ∠C = 3 ∠B = 2(∠B + ∠A) ∠B = 2 ∠A+2 ∠B ∠B=2 ∠A ∠A – ∠B= 0- – – – – – – – – – – – (i) We know, the sum of all the interior angles of a triangle is 180^{O}. Thus, ∠ A +∠B+ ∠C = 180^{O} ∠A + ∠B +3 ∠B = 180^{O} ∠A + 4 ∠B = 180^{O}– – – – – – – – – – – – – – -(ii) Multiplying 4 to equation (i) , we get 8 ∠A – 4 ∠B = 0- – – – – – – – – – – – (iii) Adding equations (iii) and (ii) we get 9 ∠A = 180^{O} ∠A = 20^{O} Using this in equation (ii), we get 20^{O}+ 4∠B = 180^{O} ∠B = 40^{O} 3∠B =∠C ∠C = 3 x 40 = 120^{O} Therefore, ∠A = 20^{O} ∠B=40^{O} ∠C = 120^{O} 0 Reply Share Share Share on Facebook Share on Twitter Share on LinkedIn Share on WhatsApp Leave an answerLeave an answerCancel reply Featured image Select file Browse Add a Video to describe the problem better. Video type Youtube Vimeo Dailymotion Facebook Choose from here the video type. Video ID Put Video ID here: https://www.youtube.com/watch?v=sdUUx5FdySs Ex: "sdUUx5FdySs". Click on image to update the captcha. Save my name, email, and website in this browser for the next time I comment. Related Questions A jar contains 24 marbles, some are green and others are blue. If a marble is drawn at ... A box contains 12 balls out of which x are black. If one ball is drawn at random ... A bag contains 5 red balls and some blue balls. If the probability of drawing a blue ball ... A die is numbered in such a way that its faces show the numbers 1, 2, 2, 3, ... Two customers Shyam and Ekta are visiting a particular shop in the same week (Tuesday to Saturday). Each ...

Given,

∠C = 3 ∠B = 2(∠B + ∠A)

∠B = 2 ∠A+2 ∠B

∠B=2 ∠A

∠A – ∠B= 0- – – – – – – – – – – – (i)

We know, the sum of all the interior angles of a triangle is 180

^{O}.Thus, ∠ A +∠B+ ∠C = 180

^{O}∠A + ∠B +3 ∠B = 180

^{O}∠A + 4 ∠B = 180

^{O}– – – – – – – – – – – – – – -(ii)Multiplying 4 to equation (i) , we get

8 ∠A – 4 ∠B = 0- – – – – – – – – – – – (iii)

Adding equations (iii) and (ii) we get

9 ∠A = 180

^{O}∠A = 20

^{O}Using this in equation (ii), we get

20

^{O}+ 4∠B = 180^{O}∠B = 40

^{O}3∠B =∠C

∠C = 3 x 40 = 120

^{O}Therefore, ∠A = 20

^{O}∠B=40

^{O}∠C = 120

^{O}