Find a quadratic equation, with integer coefficients, such that one of the roots is (13 - sqrt(131))/4.
The other root will be (13 + sqrt131)/4
So you have (x -(13+ sqrt131)/4)(x-(13-sqrt131)/4) expand and simplify
x^2 - 13/2 x + 38/16 multiply by 8 to get integer coefficients
8x^2 - 52x+ 19