No products in the cart.

AB is a diameter and AC …

CBSE, JEE, NEET, CUET

CBSE, JEE, NEET, CUET

Question Bank, Mock Tests, Exam Papers

NCERT Solutions, Sample Papers, Notes, Videos

AB is a diameter and AC is a chord of a circle with centre O such that angle BAC=30 the tangent to the circle at C intersectsAB produced in D show that BC=BD
  • 1 answers

Sia ? 6 years, 6 months ago

Given: A circle with centre O. A tangent CD at C.
Diameter AB is produced to D.
BC and AC chords are joined, ∠BAC = 30°


To prove: BC = BD
Proof: DC is tangent at C and, CB is chord at C.
Therefore, ∠DCB = ∠BAC [∠s in alternate segment of a circle]
⇒ ∠DCB = 30° …(i) [∵ ∠BAC = 30° (Given)]
AOB is diameter. [Given]
Therefore, ∠BCA = 90° [Angle in s semi circle]
Therefore, ∠ABC = 180° - 90° - 30° = 60°
In ΔBDC,
Exterior ∠B = ∠D + ∠BCD
⇒ 60° = ∠D + 30°
⇒ ∠D = 30° …(ii)
Therefore, ∠DCB = ∠D = 30° [From (i), (ii)]
⇒ BD = BC [∵ Sides opposite to equal angles are equal in a triangle]
Hence, proved.

https://examin8.com Test

Related Questions

Prove that root 8 is an irration number
  • 2 answers
(A + B )²
  • 1 answers
Find the nature of quadratic equation x^2 +x -5 =0
  • 0 answers
Venu Gopal has twice
  • 0 answers
sin60° cos 30°+ cos60° sin 30°
  • 2 answers
X-y=5
  • 1 answers

myCBSEguide App

myCBSEguide

Trusted by 1 Crore+ Students

Test Generator

Test Generator

Create papers online. It's FREE.

CUET Mock Tests

CUET Mock Tests

75,000+ questions to practice only on myCBSEguide app

Download myCBSEguide App