# Finding a tangent line

- Author:
- Jeff Willets

- Topic:
- Tangent Line or Tangent

Determine the equation of the tangent line of f(x) through point A. Type this into the input bar.
Notation:
x(A) is the x-coordinate of A. y(A) is the y-coordinate of A.
f'(x) is the derivative of f(x). At what specific point do you want to evaluate it? How will you do that?
Then construct the tangent line to f(x) at point A. This should pass the drag test, meaning that as you drag point A, the tangent line should move with it. If you don't see a different line, you did it correctly.