point moves along a curve y=2x^2+1 in such a way that the y value is decreasing at the rate of 2 units per sec. at what rate is x changing when x=3/2.

y' = 4x so F'(3/2)= m = 6

so slope=6 and f(3/2) = y= 11/2

point slope formula = y-(11/2) = 6(x-(3/2)) = y= 12x/2 -7/2

so do I set x=0 to find rate of change for x?