What problem I don't see anything
H = 4(x + 3y) + 2
H = 4x + 12y + 2
H - 12y - 2 = 4x
(H - 12y - 2) / 4 = x or 1/4H - 3y - 1/2 = x
Yes, you can; based on the inherent assumption that the "two radicals that have negative values" are, in fact, "imaginary numbers" .
Take, for example, the commonly known "imaginary number": "i" ; which represents the "imaginary number" ; " √-1 " .
Since: "i = √-1" ;
Note that: " i² = (√-1)² = √-1 * √-1 = √(-1*-1) = √1 = 1 .
__________________________________________________
Answer:
Length between two points:

28 : 12
or in reduced form
7 : 3