[The KG9 Kid]

"... BTW, what's the square root of XIX?"

If the Romans defined numbers smaller than "I" (One), which they didn't, and therefore understood the decimal point in a non-duodecimal base10 numeric system, which they didn't, we can express the square root of the Roman number 29 in the following anachronistic way:

V.MMMDCCCLI

[castlebrew]

XXIX or IXXX = 29

XIX = 19

the answer would be IV and change...