Question

In triangle PQR ​∠​ P:​ ∠​ Q:​ ∠​ R=3:2:1 and PQ​║RD. Find measure of ​∠ERD

Answer 1

Answer:

As per the diagram, lines CD∣∣EF and CE is transveral.

We know that sum of interior angles is equal to 180

o

∠ECD+∠CEF=180

o

∠ECD+130

o

=180

o

∠ECD=180−130

o

∠ECD=50

o

As per the diagram, lines AB∣∣CD and CA is transveral.

We know that alternate angles are equal.

∠BAC=∠ACD

∠BAC=∠ACE+∠ECD

70

o

=∠ACE+50

o

20

o

=∠ACE

∴∠ACE=20

o