Question 1123292
<br>
Draw the circle with the two parallel chords, and draw the diameter of the circle that is parallel to the two chords.  Draw the radius that is perpendicular to the two chords, and draw a radius to one endpoint of each of the chords.<br>
The distance of the 18cm chord from the center of the circle is the other leg of a right triangle with one leg 9 and hypotenuse 10; that distance is {{{sqrt(19)}}}.<br>
The distance of the 5cm chord from the center of the circle is the other leg of a right triangle with one leg 2.5 and hypotenuse 10; that distance is {{{5*sqrt(15)/2}}}.<br>
If the two chords are on the same side of the center, then the distance between them is {{{5*sqrt(15)/2-sqrt(19)}}}.<br>
If the two chords are on opposite sides of the center, then the distance between them is {{{5*sqrt(15)/2+sqrt(19)}}}.<br>