Education Technology

Estimating Slope of a Tangent Line

Activity Overview

Students examine the graph of y = x2 and secant line pq.

Key Steps

  • Image

    In this activity, students will estimate the slope of a tangent line to a curve by using the secant line between two points on the graph of y = x2.

  • Image

    First, they will see the effect on the slope of the secant line as the two points are moved closer to each other. They will collect the points in a table of values and calculate the slope for each set of points.

  • Image

    Finally, they will develop an expression to estimate the slope of the tangent line at the point (1, 1) by using the slope formula.