Question 1135519
based on the following reference, i think you also need the central angle formed by the chord.


<a href = "https://www.ck12.org/trigonometry/Length-of-a-Chord/lesson/Length-of-a-Chord-TRIG/" target = "_blank">https://www.ck12.org/trigonometry/Length-of-a-Chord/lesson/Length-of-a-Chord-TRIG/</a>


the reference uses radians, but the same concept applies with degrees.


otherwise, the length of the chord could be any length up to the length of the diameter which would, in this case, be equal to 10.


if you have the central angle, then you can find the length of the chord, because you can split the chord in half by taking a line segment from the center of the circle to intersect with the chord at a right angle.


this splits the chord in half.


it also forms a two right triangles, each of which will have an angle equal to half the central angle.


then you can find the length of half the chord by using sine of half the angle equals half the length of the chord divided by the radius.


solve for half the length of the chord to be equal to the radius * half the central angle.


multiply that by two and you have the length of the chord.


two examples:


the central angle is 90 degrees.


the central angle is 140 degrees.


see the attached diagram and formula, assuming the radius is 5 centimeters.


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