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Its the simple one

We know the area of circle but doesn't know the dimension of perpendicular and base of triangle. So A and D are out.
We know the triangle is 30-60-90 but we don't know any of the side to calculate the radii of circle. So B is out.
By combining we know the all the side i.e. radii of the circle. So C is sufficient
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Statement #1: this gives us the area of the triangle, but the angles could be anything, and so the sides could have an array of different values. Statement #1, alone and by itself, is insufficient.

Statement #2: this statement would allow us to figure out all three angles of triangle ABC, but you need a length to find a length. Without any length given, we can’t find the length of BC or the circumference. Statement #2, alone and by itself, is insufficient.

Statements #1 & #2 combined: Now, with both statements, we know ABC is a , and we know its area, so we could figure out the side lengths, which would allow us to figure out the diameter & circumference. Combined, the statements are sufficient.

Answer = C.[/quote]

I'm sorry but I really dont understand why the correct answer isn't A. We know that BAC is 90 degree, and we know that the inscribed angle C is equal to 1/2 of the degree of angle B. Therefore we already know that this its a 30,60,90 triangle.
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Statement #1: this gives us the area of the triangle, but the angles could be anything, and so the sides could have an array of different values. Statement #1, alone and by itself, is insufficient.

Statement #2: this statement would allow us to figure out all three angles of triangle ABC, but you need a length to find a length. Without any length given, we can’t find the length of BC or the circumference. Statement #2, alone and by itself, is insufficient.

Statements #1 & #2 combined: Now, with both statements, we know ABC is a , and we know its area, so we could figure out the side lengths, which would allow us to figure out the diameter & circumference. Combined, the statements are sufficient.

Answer = C.

I'm sorry but I really dont understand why the correct answer isn't A. We know that BAC is 90 degree, and we know that the inscribed angle C is equal to 1/2 of the degree of angle B. Therefore we already know that this its a 30,60,90 triangle.

The highlighted part is not correct. Are you saying that all right triangles inscribed in a circle are 30-60-90 triangles? That's not true.

Inscribed angle ACB is half the measure of the central angle AOB, not another inscribed angle ABC.
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I have a silly doubt regarding the C answer.

Since now we know that together they're 30-6-90 and the area, to further find the actual diameter, basically the sides, do we use
1/2 x B x H = 16√3
So,
1/2 x AB² x AC² = 16√3

1/2 x X² x √3X²= 16√3?
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chavantusharr
I have a silly doubt regarding the C answer.

Since now we know that together they're 30-6-90 and the area, to further find the actual diameter, basically the sides, do we use
1/2 x B x H = 16√3
So,
1/2 x AB² x AC² = 16√3

1/2 x X² x √3X²= 16√3?

Why do you square the sides?

\(\frac{1}{2}*AB*BC = 16\sqrt{3}\);

\(\frac{1}{2}*AB*(AB*\sqrt{3}) = 16\sqrt{3}\);

\(AB^2 = 32\).

\(AB=4\sqrt{2}\). Hence, \(BC=4\sqrt{2}*\sqrt{3}=4\sqrt{6}\) and \(AC =4\sqrt{2}*2=8\sqrt{2}\).
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Bunuel Thankyou. I was probably too worked out, was not thinking clearly. Thankyou though. It's pretty clear now.
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The trick in this is not falling for the 30-60-90 trap in statement 1.

Unless we are given the actual side ratios then the area can be constituted by many different side values.
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