In Exercises $15-18,$ apply Newton's Method to approximate the $x$ -value(s) of the indicated point(s) of intersection of the two graphs. Continue the process until two successive approximations differ by less than 0.001. [Hint: Let $h(x)=f(x)-g(x) . ]$
$$f(x)=2 x+1$$
$$g(x)=\sqrt{x+4}$$