Estimate the slope of the tangent line (rate of change) to f(x)=x2\displaystyle {f{{\left({x}\right)}}}={x}^{{2}} at x=1\displaystyle {x}=-{1} by finding the slopes of the secant lines through the points:

  1. (2,4)\displaystyle {\left(-{2},{4}\right)} and (0,0)\displaystyle {\left({0},{0}\right)}

    secant slope, msec=\displaystyle {m}_{{{\sec}}}=

  2. (1.5,2.25)\displaystyle {\left(-{1.5},{2.25}\right)} and (0.5,0.25)\displaystyle {\left(-{0.5},{0.25}\right)}

    secant slope, msec=\displaystyle {m}_{{{\sec}}}=