Answer:
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Midpoint of the chord, one of the endpoints of the chord and the center form a right triangle with the radius being its hypotenuse.
The sides of the triangle are:
- One leg is the half-chord, 30/2 = 15 cm;
- Hypotenuse is the half-diameter, 12/2 = 16 cm;
- The other leg is the distance from the center to the chord, x cm.
Use Pythagorean theorem to find the value of x: