area, in squared units

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area, in squared units

by sanju09 » Sat Jun 19, 2010 3:23 am
Points A (8, 0) and B (0, 6) are points in the standard coordinate plane. Let a be the area, in squared units, of a circle that passes through A and B. Which of the following is the set of all possible values of a?
(A) a < 25 π
(B) a > 10
(C) a > 48
(D) a ≥ 25 π
(E) a ≥ 100 π
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by kvcpk » Sat Jun 19, 2010 3:45 am
sanju09 wrote:Points A (8, 0) and B (0, 6) are points in the standard coordinate plane. Let a be the area, in squared units, of a circle that passes through A and B. Which of the following is the set of all possible values of a?
(A) a < 25 π
(B) a > 10
(C) a > 48
(D) a ≥ 25 π
(E) a ≥ 100 π
The line joining A and B will be the chord of the circle..
So lenght of that line is 10.

We know that the longest chord of a circle is diameter. So assume this is diameter.
In that case area will be 25Pi

So any circle passing thru them shud have an area greater than or equal to 25pi

Answer D