9514 1404 393
Answer:
12 cm
Step-by-step explanation:
The distance to the chord is the median of an isosceles right triangle with hypotenuse 20 and leg 16. This 5:4 ratio suggests the other leg of that right triangle would make the ratios 3 : 4 : 5, so is 12.
The chords are 12 cm from the center.
_____
You can, of course, use the Pythagorean theorem. If c is half the chord length and d is the distance to the chord, you have ...
c² + d² = r²
16² + d² = 20²
d² = 400 -256 = 144
d = √144 = 12 . . . . . cm
