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Question
In the given figure, x + y =
Options
270
230
210
190°
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Solution
In the given figure, we need to find x+ y
Here, AB and CD are straight lines intersecting at point O, so using the property, “vertically opposite angles are equal”, we get,
∠BOD = ∠AOC
∠BOD = 40°
Further, applying the property, “an exterior angle of a triangle is equal to the sum of the two opposite interior angles”, in ΔAOC, we get,
x° = ∠ACO + ∠AOC
x° = 80° + 40°
x° = 120°
Similarly, in ΔBOD
y° = ∠BOD + ∠BDO
y° = 40° + 70°
y° = 110°
Thus,
x° + y° = 120° + 110°
x° + y° = 230°
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