Home Maths Straight Line General A triangle is formed by the lines whose equa…
Maths Straight Line General Subjective Type
Published on: August 14, 2026

A triangle is formed by the lines whose equations are AB : x + y – 5 = 0, BC :
x + 7y – 7 = 0 and CA : 7x + y + 14 = 0. Find the bisector of the interior angle at B and the exterior angle at C. Determine the nature of the interior angle at A and find the equation of the bisector.

Share this question

For Instagram sharing, use “Apps” on mobile or copy the link.

Text Solution

Verified by Experts
The correct answer is:
CHECK THE SOLUTION.

3x + 6y – 16 = 0; 8x + 8y + 7 = 0 ; 12x + 6y – 11 = 0

Sol.  The slopes of the lines AB, BC and CA are –1, – and –7 respectively

Let m 1 = – , m 2 = –1, m 3 = – 7  m 1 > m 2 > m 3

∴ tangent of internal angles of the triangle are

tanA = , tanB = , tanC =

⇒ tan A = , tan B = and tan C = –

∴ interior angles A and B are acute and interior angle C is obtuse

∴ internal bisector of B = acute bisector of B ≡ 3x + 6y – 16 = 0

External bisector of C ≡ acute bisector of C ≡ 8x + 8y + 7 = 0

Internal bisector of A ≡ acute bisector of A ≡ 12x + 6y – 11 = 0

──────────────────────────────────────────────────────────────────────────────────────────

Prepare Smarter with CGP Edu

Get practice questions, solutions, and test series in one place.

Write a Review

Share your experience with this question and solution.

Commentary

Send your comment, doubt, correction, or feedback to admin.

Student Reviews

What students say about this solution

No reviews yet. Be the first to write a review.

Similar Questions

Explore conceptually related problems

CG
CGP Question Assistant Question Bank + AI Help
Hi! Type your question or upload one screenshot. First I will search related questions from CGP Edu Question Bank. If none match, type YES and I will solve it with AI.
Upload only one screenshot at a time. Flow: Question Bank first → If not matched, type YES for AI solution.