What is the formula for tangent line? By formula i mean the layout as well. I remember that i was supposed to substract something from f(x). I am having trouble remembering and the answer i found only told me that tangent line was the derivative.

The equation of the tangent line to the graph of a function $y=f(x)$ through the point $(x_0,f(x_0))$ is given by $y=f'(x_0)(x-x_0)+f(x_0).$