Slope of a Tangent as a Limit grade 12 calculus Hello, I don't know where I went wrong with this problem but, I've been at this for so long my brain is jello. Help is appreciated

I need to determine the slope of the tangent to the curve at the given point.

(sr=square root)

y=sr x-7 (16,3)

My work:

mtan= lim h-&gt;0 f(a+h)- f(a)/h ;h cannot =0

= lim h-&gt;0   f(16+h)- f(16)/h


= lim h-&gt;0 (sr16+h-7)- (sr16-7) /h


= lim h-&gt;0  (sr9+h) -3 /h X (sr 9+h)/(sr 9+h)


= lim h-&gt;0  9+h- 3(sr9+h)/h(sr9+h)


= 7


The answer is supposed to be 1/6

