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Question
In the given figure, what is y in terms of x?

Options
- \[\frac{3}{2}x\]
- \[\frac{4}{3}x\]
- x
\[\frac{3}{4}x\]
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Solution
In the given figure, we need to find y in terms of x

Now, using the property, “an exterior angle of the triangle is equal to the sum of the two opposite interior angles”, we get
In ΔABC
ext∠ACD = ∠CAB + ∠CBA
ext∠ACD = x + 2x
ext∠ACD =3x ..........(1)
Similarly, in ΔOCD
ext∠AOD = ∠OCD + ∠CDO
3y = ∠OCD + y (using 1)
3y - y = 3x
2y = 3x
`y = 3/2 x`
Thus, `y = 3/2x `
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