In the below Fig. OA and OB are opposite rays:
(i) if x=25∘, what is the value of y?
Given: x=25∘
From the given figure,
∠AOC=(2y+5)∘ and ∠BOC=3x∘
Since, ∠AOC and ∠BOC form a linear pair
∴∠AOC+∠BOC=180∘
(2y+5)∘+3x∘=180
2y+5∘+3(25∘)=180∘
2y+80∘=180∘
2y=180∘−80∘
2y=100∘
y=50∘
Hence, the value of y=50∘.