Rays and are drawn on opposite sides of ray such that and

MATHEMATICS · Subjective · CBSE · Mathematics · Lines and Angles · Lines and Angles

Problem

Rays

DB

and

DC

are drawn on opposite sides of ray

DA

such that

\angle BDA = 42^{\circ}

and

\angle ADC = 138^{\circ}

. Prove that points

B, D

and

C

are collinear.