Question

2. In the given figure, AODC“ AOBA
BOC = 125°, CDO = 70°
Find OAB​

Answer 1

Step-by-step explanation:

∠DOC+125

o

=180

o

(linear pair)

⇒ ∠DOC=180

o

−125

o

=55

o

In △DOC

∠DCO+∠CDO+∠DOC=180

o

(sum of three angles of △ODC)

⇒ ∠DCO+70

o

+55

o

=180

o

⇒ ∠DCO+125

o

=180

o

⇒ ∠DCO=180

o

−125

o

=55

o

Now we are given that △ODC∼△OBA

⇒ ∠OCD=∠OAB (Corresponding angles of similar triangles)

⇒ ∠OAB=∠OCD=∠DCO=55

o

i.e., ∠OAB=55

o

Hence we have,

∠DOC=55

o

;∠DCO=55

o

;∠OAB=55

o