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MathRevolution
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ArunSharma12
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MathRevolution
Solution:

Since PT is tangent to the circle, we have ∠OTP = \(90^°\) and ∠AOT = \(180^°\) - \(20^°\)- \(90^°\) = \(70^°\).

Since the triangle is an isosceles triangle with AO = OT, we have ∠OTA = ∠OAT = ∠x.

Thus ∠x = \(\frac{(180^°- 70^°)}{2}\) = \(55^°\).

Therefore, D is the correct answer.

Answer: D

Is there a rule why the circle must also go through a and build an isoceles traingle? I mean just because the drawing looks like it is not enough to confirm that it actually does?
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