I can prove that statement 2 is sufficient, but still have a feeling that D should be the answer
ST1 can't solve for this atatement
ST 2 Since DE || CA the angles of this two triangles are equal. since CA and CB (both are radius) - angle CAB=CBA. So angle DBE=DEB and DE should be equal DB.
triangle
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hongwang9703
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i think the answer should be D, and here are the reasons why, Statement A, by itself, should be sufficient.
DB is the diameter of the circle, thus making angle DEB 90 degrees. (from the properties of triangles in circles)
If x = 60, then angle cba and cab are both 60 degrees as well, because ca=cb, as both are radius.
thus we know that ANGLE DBE is a 30-60-90 triangle, therefore DE = 3.5SQRT(3)
however, if i am wrong, then i am wrong with respect to stating that angle DEB is 90 degrees. Maybe that rule only applies when the question explicitly states that the triangle is inscribed in a circle.
please let me know kind sir,miss.
DB is the diameter of the circle, thus making angle DEB 90 degrees. (from the properties of triangles in circles)
If x = 60, then angle cba and cab are both 60 degrees as well, because ca=cb, as both are radius.
thus we know that ANGLE DBE is a 30-60-90 triangle, therefore DE = 3.5SQRT(3)
however, if i am wrong, then i am wrong with respect to stating that angle DEB is 90 degrees. Maybe that rule only applies when the question explicitly states that the triangle is inscribed in a circle.
please let me know kind sir,miss.
i got utterly defeated by the gmat.
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Brent@GMATPrepNow
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Here's my solutionadam15 wrote:In the figure to the right, if point C is the center of the circle and DB = 7, what is the length of DE in triangle EDB?
(1) x = 60°
(2) DE || CA
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nithi_mystics
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This is true only if the point E lies on the circle.hongwang9703 wrote:i think the answer should be D, and here are the reasons why, Statement A, by itself, should be sufficient.
DB is the diameter of the circle, thus making angle DEB 90 degrees. (from the properties of triangles in circles)
If x = 60, then angle cba and cab are both 60 degrees as well, because ca=cb, as both are radius.
thus we know that ANGLE DBE is a 30-60-90 triangle, therefore DE = 3.5SQRT(3)
however, if i am wrong, then i am wrong with respect to stating that angle DEB is 90 degrees. Maybe that rule only applies when the question explicitly states that the triangle is inscribed in a circle.
please let me know kind sir,miss.
Thanks
Nithi
Nithi
