Answer
Step-by-step explanation
Inside the circle there is a square of sides 9 units.
The diagonal of this square is the radius of the circle and can be found using pythagorous theorem
c²=a²+b²
c = √(9²+9²)
= √(81+81)
= √162
= 12.7
Now we can use the properties of circle with two chords intersecting inside the circle.
12.7+9=21.7
(12.7×2)-21.7 = 25.4-21.7
= 3.7
3.7×21.7 = x × x
y² = 80.29
y =√80.29
= 8.96
x = 2y
= 8.96×2
= 17.9