Use app×
Join Bloom Tuition
One on One Online Tuition
JEE MAIN 2025 Foundation Course
NEET 2025 Foundation Course
CLASS 12 FOUNDATION COURSE
CLASS 10 FOUNDATION COURSE
CLASS 9 FOUNDATION COURSE
CLASS 8 FOUNDATION COURSE
0 votes
68 views
in Linear Equations by (44.9k points)
closed by
In a ` Delta ABC, angle C = 3, angle B = 2 (angle A + angle B)`, then ` angle B ` = ?

1 Answer

0 votes
by (43.8k points)
selected by
 
Best answer
Let ` angle A= x ^(@) and angle B = y^(@)`.
Then, ` angle C = 3 angle B = ( 3y) ^(@)`
Now, ` angle C = 2 (angle A + angle B )`
` rArr 3y = 2 (x + y ) rArr 2x - y = 0 " " `… (i)
We know that the sum of the angles of a triangle is ` 180^(@)`
` therefore angle A + angle B + angle C = 180 ^(@) rArr x + y + 3y = 180`
` " " rArr x + 4y = 180" " `... (ii)
On multiplying (i) by 4 and adding the result with (ii), we get
` 8x + x = 180 rArr x = 20`.
Putting ` x = 20 ` in ( i ), we get `y = ( 2 xx 20 ) = 40 `
Thus, ` x = 20 and y = 40 `
` therefore " " angle A = 20 ^(@), angle B = 40 ^(@) and angle C = ( 3xx 40 ^(@)) = 120 ^(@)`

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.

...