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Question
In the given figure, what is the value of x?
Options
35
45
50
60
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Solution
In the given figure, we need to find the value of x.
Here, DBA is a straight line, so using the property, “angles forming a linear pair are supplementary”, we get,
∠CBA + ∠CBD = 180°
7y + 5y = 180°
12y = 180°
`y = (180°)/12`
y = 15°
Now, applying the value of y in ∠CBA and ∠BCA
∠BCA = 3y
= 3(15°)
= 45°
Also,
∠CBA = 5y
= 5(15°)
= 75°
Further, applying angle sum property of the triangle
In ΔABC
∠A + ∠B +∠C = 180°
x + 75° + 45° = 180°
x + 120°= 180°
x = 180° - 120°
x = 60°
Thus, x = 60°
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