If a 32-inch chord is drawn in a circle of radius...

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If a 32-inch chord is drawn in a circle of radius 20 inches, how far is the chord from the center of the circle?

A. 4 inches
B. 6 inches
C. 8 inches
D. 10 inches
E. 12 inches

The OA is E.

Please, can any expert explain this PS question for me? I have many difficulties to understand why that is the correct answer. Thanks.
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by [email protected] » Tue Nov 28, 2017 11:47 am
Hi swerve,

When dealing with Geometry questions, it can often help to draw a picture - so that you can keep track of the information that you're given and "add" information as needed. I'm going to give you a few 'hints' so that you can retry this question on your own:

1) Draw a circle with the diameter/radii and label those measurements.
2) Draw a chord below the diameter (a 'chord' connects any two points on a circle). You'll find it easiest to draw the chord parallel to the diameter.
3) Draw two new radii from the center of the circle to the ends of the chord and label those measurements. You now have an isosceles triangle.
4) Draw a line 'cutting' the isosceles triangle in half. You now have two RIGHT TRIANGLES. Based on all of the numbers you have to work with, what are the side lengths of those triangles....? You should be able to answer the given question.

Final Answer: E

GMAT assassins aren't born, they're made,
Rich
Contact Rich at [email protected]
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