### 2.A. Secant Lines and Tangent Lines

 Secant lines are lines that are based off of two points on a function. Finding the slope of a secant line can be found using the slope equation:    $\dpi{100} m=\frac{y-y_0}{x-x_0}$Tangent lines are lines that are based off of one point on a function. Finding the slope of a tangent line can be found using the derivative equation:    Alternative derivative equation:    Key TermsEssential QuestionsHow is the slope of a tangent line calculated?