Question

Use linear approximation to approximate square root of 49.1
Let f(x) = square root of x. the equation of the tangent line to f(x) at x= 49 can be written in the form y=mx+b
m is:
b is:
the first thing is did was plug in
f(49.1) = f'(40)(49.1-49) + square root of 49. Not sure if this is the right step

Answer 1

If you had said "f'(49)", you would have had it. "40" just sort of dropped in from the sky.

Answer 2

that's what I meant. whoops

Answer 3

There you go!