Geometryhard · Past Paper
A tangent PA is drawn from an external point P to a circle with center O. If the radius of the circle is 5 cm and the angle APO is 30 degrees, what is the length of OP?
A5 cm
B10 cm
C5*sqrt(3) cm
D10*sqrt(3) cm
✓ Correct Answer: B — 10 cm
In triangle OAP, angle A is 90. sin(30) = OA/OP = 5/OP. 1/2 = 5/OP, so OP = 10 cm.
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