Question

In Fig. 8.122, AOB is a straight line. If ∠AOC +∠BOD = 85°, then ∠COD =
A. 85°
B. 90°
C. 95°
D. 100°

Answer 1

Answer:

angle COD=180-85

=95

so, option C is correct.

Answer 2

Concept :  

Linear pair of angles:

If Non common arms of two adjacent angles form a line, then these angles are called linear pair of angles.

 

 

Given : AOB is a straight line. ∠AOC + ∠BOD = 85°, then  

 

To find : ∠COD  

Proof:  

∠AOC + ∠BOC  = 180° (Linear pair)

∠AOC + (∠COD + ∠BOD) = 180°  

(∠AOC + ∠BOD) + ∠COD = 180°

85° + ∠COD = 180°

[∠AOC + ∠BOD = 85°]

∠COD = 180° -  85°

∠COD = 95°

Hence ∠COD is  95°.

Among the given options option (C) 95° is correct.

HOPE THIS ANSWER WILL HELP YOU…..

 

 

Some questions of this chapter :

In the given figure, lines AB and CD intersect at O. If and find ∠BOE and reflex ∠COE.

https://brainly.in/question/1389703

 

Two straight lines AB and CD cut each other at O. If ∠BOD = 63°, the ∠BOC =

A. 63°

B. 117°

C. 17°

D. 153°

https://brainly.in/question/15906408