Answer:
10.4
Explanation:
If you slide the cut left or right so that it is the long leg of a right triangle with short leg 6", you find that right triangle is a 30°-60°-90° triangle. The length of the cut is √3 times the length of the short leg, so is ...
... 6√3 in ≈ 10.3923 in ≈ 10.4 in