x^2-6x+1=(3x+5)/2

Now this one is real easy compared to the previous ones

x^2 - 6x + 1 = (3x+5)/2
times 2

2x^2 - 12x + 2 = 3x + 5
2x^2 - 15x - 3 = 0
using the quad formula

x = (15 ± √249)/4