Q. 185.0( 2 Votes )

# In Fig. 9.44, *x + y =*

A. 270

B. 230

C. 210

D. 190°

Answer :

By exterior angle theorem,

In

∠OCA + ∠AOC = x

x = 80^{o} + 40^{o}

= 120^{o}

∠AOC = ∠DOB (Vertically opposite angle)

∠DOB = 40^{o}

By exterior angle theorem,

In

y = ∠BOD + ∠ODB

= 40^{o} + 70^{o}

= 110^{o}

Now, x + y = 230^{o}

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