y
2 = 6x

y
2 = 4. 6x/4

y
2 = 4.(3/2)x
Comparing above equation with general equation of parabola y2 = 4ax, we get
a = 3/2
We know that equation of any tangent to parabola y2 = 4ax is
y = mx + a/m , where m is the slope of the tangent.
Here, equation of tangent would be y = mx + (3/2)/m
i.e. y = mx + 3/2m ….(1)

It passes through (3/2,5), i.e., (3/2,5) satisfies eq. (1)

5 = 3m/2 + 3/2m

5 = (3/2)(m + 1/m)

10/3 = (m
2 + 1)/m
Solving above equation, we get
3m2 – 10m +3 = 0

(3m – 1)(m – 3) = 0
m = 1/3 or m = 3
Thus, the required slopes are 1/3 and 3.