Answer:
Oblique asymptote at y = 3x+14
Explanation:

The degree of numerator is 2
degree of denominator is 1
When the degree of numerator is greater than the degree of denominator by 1 then there is a slant asymptote
To find slant asymptote we divide by long division
3x +14
-------------------------------
x-4 3x^2+ 2x -5
3x^2-12x
---------------------------- (subtract)
+14x - 5
14x - 56
-------------------------------(subtract)
51
Oblique asymptote at y = 3x+14