Question 196553
A chord of 12cm subtends an angle of 78.2 at the centre of a circle. Find the radius of the circle
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Connecting the center of the circle with the 2 ends of the chord makes an isc.. triangle.
Half of that is a right triangle.  The angle at the center of the circle is 39.1º and 1/2 the chord is 6 cm.
6 = r*sin(39.1)
r = 6/sin(39.1)
r = ~ 9.5136 cm